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  1. 1. Jarred Kelenic | OF
    Jarred Kelenic
    Born: Jul 16, 1999
    Bats: L Throws: L
    Ht.: 6'0" Wt.: 196
    Drafted: HS--Waukesha, Wis., 2018 (1st).
    Signed By: Chris Hervey (Mets).
    Minors: .291/.363/.540 | 23 HR | 20 SB | 443 AB

    Track Record: Kelenic won a pair of gold medals for USA Baseball's 18U National Team, then graduated early from his Wisconsin high school to train for the 2018 draft. His pedigree and dedication paid off when the Mets drafted him sixth overall as the first prep player off the board and signed him for a franchise-record $4.5 million bonus. After one summer in the Mets organization, Kelenic was the jewel of the prospect haul for the Mariners in the trade that sent Robinson Cano and Edwin Diaz to New York.

    Scouting Report: Kelenic immediately became the Mariners' best position prospect after the trade and could develop into a center fielder with five average or better tools. He has a long track record with wood bats and a simple, quick lefthanded swing honed by countless hours in the batting cage. His feel for the barrel gives him a plus hit tool, while his strong batting eye makes him an on-base threat who will bat toward the top of a lineup. Kelenic's raw power is at least plus and as he tweaks his approach and launch angle he should get to above-average pop in games. Projected as an average runner, his raw speed might be a bit short of the center field prototype, but he has the instincts to stick there as a solid-average defender. An above-average arm could make him a plus defender on a corner

    The Future: Kelenic turned 19 in July after the draft and was old for his high school class, but that should help ease his transition to low Class A West Virginia in 2019.

  2. 2. Julio Rodriguez | OF
    Julio Rodriguez
    Born: Dec 29, 2000
    Bats: R Throws: R
    Ht.: 6'4" Wt.: 225
    Drafted: Signed: Dominican Republic, 2017.
    Signed By: Eddy Toledo/Tim Kissner
    Minors: .329/.394/.541 | 12 HR | 1 SB | 331 AB

    Track Record: Rodriguez dominated the Dominican Summer League just one year after signing with the Mariners for $1.75 million. Named the team MVP after posting a .929 OPS, Rodriguez's season ended in mid-August when he injured a foot attempting to steal a base, but he was able to participate in the Mariners' fall development programs.

    Scouting Report: A smart hitter for his age with very good control of the zone and the ability make adjustments at the plate, Rodriguez's loudest tool is his plus-plus raw power, which already ranks among the best in the organization. His rhythmic righthanded swing gives him a solid bat path through the zone. While only an average runner, he runs the bases well. Rodriguez should develop solid instincts and routes in right field, where he should be at least an average defender. He gained enough arm strength since signing that his arm now earns a 70 grade.

    The Future: Rodriguez has as much upside as any prospect in the Mariners' organization. His advanced baseball acumen and tool set may allow him to start his U.S. career at short-season Everett or perhaps even low Class A West Virginia. It would not be a surprise to see Rodriguez at the top of the Mariners' prospect list heading into 2020.

  3. 3. Justus Sheffield | LHP
    Justus Sheffield
    Born: May 13, 1996
    Bats: L Throws: L
    Ht.: 6'0" Wt.: 200
    Drafted: HS--Tullahoma, Tenn., 2014 (1st round).
    Signed By: Chuck Bartlett (Indians).
    Minors: 6-8 | 3.95 ERA | 120 SO | 51 BB | 123.0 IP

    Track Record: Sheffield ranked as the Yankees' top prospect heading into the 2018 offseason before being the key acquisition in the trade to the Mariners for ace James Paxton. Sheffield signed with the Indians out of high school as a first-round pick and was traded to the Yankees with Clint Frazier in 2016 to help the Indians acquire reliever Andrew Miller. Sheffield missed time in 2017 with an oblique issue and missed one start in 2018 with tightness in his left shoulder. The Yankees moved him to the bullpen in August to prepare him for a bullpen role in New York in September. He struggled to throw strikes in three late-season outings in New York.

    Scouting Report: Sheffield is a starter who attacks hitters like a late-inning reliever. Everything he throws is hard and he shows little finesse. He attacks hitters with an effort-filled delivery. A generation ago, that would likely lead to a move to the bullpen, but today Sheffield will get to prove that his all-out approach can work for five to six innings per start. After much debate, the Yankees sent Sheffield back to Double-A Trenton to begin the 2018 season so he could continue to sharpen the command of his mid-90s fastball. He worked to add two-plane break to his mid-80s slider. He was successful at times in this regard, with the pitch showing more depth in particular during his stint in the big leagues. Now, he'll need to work to repeat the mechanics that allowed him to make this alteration. His 87-89 mph changeup had been too firm for the Yankees' taste, and they wanted to see him figure out a grip that would allow him to get more separation between it and his fastball. The Yankees said that in spurts he showed the ability to dial back his offspeed pitches, but sometimes, especially when he moved to the bullpen, adrenaline took over and he reverted back to throwing everything as hard as possible. Expect to see better results now that his major league debut is behind him.

    The Future: Sheffield will likely return to Triple-A in 2019, but this time across the country in Tacoma. He should be making big league starts for the Mariners at some point in 2019.

  4. 4. Logan Gilbert | RHP
    Logan Gilbert
    Born: May 5, 1997
    Bats: R Throws: R
    Ht.: 6'6" Wt.: 225
    Drafted: Stetson, 2018 (1st round).
    Signed By: Rob Mummau.
    Minors: 10-4 | 2.25 ERA | 157 SO | 31 BB | 128.0 IP

    Track Record: Gilbert excelled at Stetson by going 23-3, 2.48 with 11.2 strikeouts per nine innings in three seasons. After signing for $3,883,800 he spent most of the summer recovering from a bout of mononucleosis and toe surgery and did not pitch professionally.

    Scouting Report: Gilbert profiles as a workhorse with a heavy power fastball with life and downward action. After pitching in the mid-90s during the 2017 Cape Cod League, his heater was more regularly in the low 90s as a college junior. But even with the diminished velocity, his fastball projects to be an above-average thanks to excellent extension in his delivery and late life on the pitch. Both of his breaking balls--a spike-curveball and a hard slider--were no better than average pitches to outside observers. The Mariners see the potential for both breaking balls to be plus, especially his curveball with two-plane action and depth. Rounding out Gilbert's arsenal is a potentially average mid-80s changeup with fade. His athleticism allows him to repeat a free-and-easy, high three-quarters arm slot.

    The Future: Gilbert should be advanced enough to jump straight to full-season ball to start his pro career in 2019, but staying behind in extended spring training to manage his innings in his first season is also a possibility.

  5. 5. Evan White | 1B
    Evan White
    Born: Apr 26, 1996
    Bats: R Throws: L
    Ht.: 6'3" Wt.: 205
    Drafted: Kentucky, 2017 (1st round).
    Signed By: Jackson Laumann.
    Minors: .296/.354/.490 | 18 HR | 2 SB | 361 AB

    Track Record: White comes by his athleticism naturally. Both his father and grandfather played in the minor leagues, and his parents were both college basketball players. Undrafted out of his Ohio high school, he earned second team All-America honors as a Kentucky junior in 2017. A career .356 hitter for the Wildcats, he also played with USA Baseball's Collegiate National Team in the summer before his junior year. The 17th overall pick in 2017, White began his pro career at short-season Everett, though his season was curtailed by a quad injury. He got in a full season in 2018, mostly at high Class A Modesto followed by six weeks in the Arizona Fall League.

    Scouting Report: White's footwork around the first base bag is so graceful that his movements there have been called ballet-like. He earns plus-plus grades for his defense. He has very good instincts and soft hands. A plus hitter with advanced skills and a plan at the plate, White is a hit-over-power type who uses all fields and makes hard contact. Questions have been raised as to whether he will hit for enough power to profile as a starting first baseman, though his above-average raw power and good exit velocities hint at a chance to exceed his average power projections. White started answering doubts about his power in the second half of 2018 by lowering his hands, keeping his bat in the hitting zone longer and staying through the ball. The results showed when he hit five of his 11 Cal League home runs in August. He has a good swing and finds the barrel a lot, and he studies opposing pitchers' tendencies.

    The Future: While he doesn't have the same power profile, White has been compared with the Dodgers' Cody Bellinger as a first baseman who could also play center field. First base is a position of need for the Mariners, so White could advance quickly. He'll advance to Double-A Arkansas in 2019 and could see time at Triple-A.

  6. 6. Justin Dunn | RHP
    Justin Dunn
    Born: Sep 22, 1995
    Bats: R Throws: R
    Ht.: 6'2" Wt.: 185
    Drafted: Boston College, 2016 (1st round).
    Signed By: Michael Pesce (Mets).
    Minors: 9-5 | 3.67 ERA | 164 SO | 40 BB | 137.3 IP

    Track Record: Dunn spent most of his time in college in the bullpen, and then scuffled in his full-season debut in the high Class A Florida State League. But after he made 24 starts while taming the FSL and reaching Double-A in 2018, his future appears firmly planted in the rotation. Based on that development, the Mariners acquired Dunn in December as one of the top prospects in the deal that sent Robinson Cano and Edwin Diaz to the Mets.

    Scouting Report: Dunn evolved from thrower to pitcher in 2018 by working his fastball to both sides of the plate and up and down in the zone at 93-95 mph from an effortless delivery. He can sink his fastball for early-count groundball outs or throw it with riding life up in the zone for swinging strikes. Dunn's slider is his go-to secondary weapon, and it flashes plus with two-plane break to neutralize righthanded hitters. He committed to throwing his changeup in 2018 and made huge strides. The mid-80s pitch fades to his arm side and bottoms out as it approaches the plate, erasing the ugly platoon split he had in 2017. His athletic motion allows him to throw first-pitch strikes and grants him access to future average control.

    The Future: Dunn is positioned to assume any role the Mariners need in the second half of 2019, be it multi-inning reliever or spot starter. Long term he has the profile of a No. 3 or 4 starter.

  7. 7. George Kirby | RHP
    George Kirby
    Born: Feb 4, 1998
    Bats: R Throws: R
    Ht.: 6'4" Wt.: 201
    Minors: 0-0 | 2.35 ERA | 25 SO | 0 BB | 23.0 IP

    One of the best strike-throwers in the country, Kirby formed an impressive one-two combination with righthander Kyle Brnovich at Elon this spring. Kirby is the higher-rated draft prospect, however, due to his slew of starter’s traits and solid four-pitch mix. While there are pitchers with louder pure stuff than the 6-foot-4, 201-pound righthander, Kirby is among the most likely 2019 draft prospects to make a major league impact because of his clean arm action and plus command. Through 11 starts and 71.2 innings this spring, Kirby had struck out 84 hitters and walked just five, which ranked as the best strikeout-to-walk ratio (16.8) in the country. While some scouts will critique the level of competition that Kirby faced in the Colonial Athletic Association and don’t expect him to miss many bats against better competition, it’s impossible to ignore his strike-throwing ability. There’s also his impressive 2018 in the Cape Cod League, where Kirby worked as a reliever and posted a 1.38 ERA over 13 innings, striking out 24 and walking only one. Kirby’s fastball has reached as high as 97 mph in the past, but this spring he’s worked mostly in the low 90s while touching 94-95 mph consistently. His fastball grades out as a plus offering because of his ability to spot it to both sides of the plate and elevate it when necessary. Kirby throws a curveball and a slider, and both pitches will flash plus at times, but they lack consistency right now and might be average pitches, at best, in a starting role. Kirby’s top offspeed pitch could be his mid-80s changeup, which he throws with conviction and consistently lands in the bottom of the strike zone. Kirby looks the part of a solid, middle- to back-of-the-rotation starter, and he should be selected in the middle of the first round this June.

  8. 8. Joeli Martinez | RHP
    Joeli Martinez
    Born: Apr 17, 2000
    Bats: R Throws: R
    Ht.: 6'3" Wt.: 180
  9. 9. Cal Raleigh | C
    Cal Raleigh
    Born: Nov 26, 1996
    Bats: B Throws: R
    Ht.: 6'3" Wt.: 215
    Drafted: Florida State, 2018 (3rd round).
    Signed By: Rob Mummau.
    Minors: .253/.323/.502 | 29 HR | 4 SB | 450 AB

    Track Record: The switch-hitting Raleigh was a three-year starter at Florida State. He hit much better as a junior, compiling a team-leading 1.030 OPS with 13 home runs to make up for a lackluster sophomore season. While Raleigh faced plenty of questions about his ability to hit with wood bats, the Mariners drafted him in the third round in 2018, attracted to his potential power bat and catcher profile.

    Scouting Report: Raleigh's carrying tool is his above-average raw power from both sides of the plate. He manages the strike zone well with a swing that is similar from both sides. The Mariners were pleasantly surprised with Raleigh's defense in his pro debut at short-season Everett, with the above-average arm and blocking techniques indicating he has a chance to be an above-average defender. He also scored well in the organization's pitch-framing metrics. Raleigh was praised for his work ethic. The son of a one-time college coach, Raleigh has been around the game all his life, and it shows in his baseball IQ.

    The Future: Raleigh will head to low Class A West Virginia with much of the rest of the Mariners' 2018 draft class. He already is the system's best catcher.

  10. 10. Kyle Lewis | OF
    Kyle Lewis
    Born: Jul 13, 1995
    Bats: R Throws: R
    Ht.: 6'4" Wt.: 210
    Drafted: Mercer, 2016 (1st round).
    Signed By: John Wiedenbauer.
    Minors: .273/.350/.412 | 11 HR | 3 SB | 454 AB

    Track Record: Lewis tore the anterior cruciate ligament in his right knee in a home plate collision in his 2016 pro debut. He has been working his way back from that injury ever since. Lewis' 2018 season got a late start when he was held back in extended spring training until May to strengthen his knee. After an appearance in the California League all-star game, Lewis moved up to Double-A Arkansas for the remainder of 2018.

    Scouting Report: At the plate Lewis is balanced and short to the ball, with loose hands and the ability to adjust to fastballs in the zone, but he sometimes looks like he's trying to make up for lost time in every at-bat. He struggled to make consistent contact after the move to Double-A and has yet to show the plus-plus raw power he had in college and his pro debut. He is a fringe-average runner because of his knee injuries. Lewis is still capable of making highlight-reel plays in the outfield, with his average speed underway and solid instincts being the strong points. His lack of first-step quickness will likely push him to right field. He has an above-average arm.

    The Future: Barring any further issues with his knee, Lewis should be ready for a full workload in 2019, likely heading back to Double-A to start the year.

  11. 11. Shed Long | 2B
    Shed Long
    Born: Aug 22, 1995
    Bats: L Throws: R
    Ht.: 5'8" Wt.: 184
    Drafted: HS--Jacksonville, Ala., 2013 (12th round).
    Signed By: Ben Jones (Reds).
    Minors: .274/.335/.460 | 9 HR | 1 SB | 226 AB

    Track Record: Long’s pro career got off to a slow start, but he took off at the plate once he moved from catcher to second base, where his athleticism plays better. He has steadily worked to improve his defense at second while consistently providing solid-average power and a discerning batting eye. After a solid showing at Double-A and the Arizona Fall League in 2018, the Mariners acquired Long from the Reds for second-rounder Josh Stowers.

    Scouting Report: Long is a bat-first player, using special bat speed and barrel manipulation to hit the ball to all fields. While he has had some issues with making consistent contact, his lefthanded bat shows signs of being above-average with future average power. His hands are very strong, which allows him to generate his bat speed. Long’s actions in the field need work, but his athleticism and average arm have helped him improve to the point where he’s a fringe-average defender. He is an average runner who is efficient stealing bases with advanced instincts, making him a double-digit home run, double-digit stolen base threat.

    The Future: Long should see regular at-bats at Triple-A Tacoma in 2019. If he continues to improve his defense, he has a chance to emerge as the Mariners' second baseman of the future.

  12. 12. Jake Fraley | OF
    Jake Fraley
    Born: May 25, 1995
    Bats: L Throws: L
    Ht.: 6'0" Wt.: 195
    Drafted: Louisiana State, 2016 (2nd round supplemental).
    Signed By: Rickey Drexler (Rays).
    Minors: .300/.366/.550 | 20 HR | 22 SB | 387 AB

    Track Record: The Mariners acquired Fraley in the trade that sent Mike Zunino to the Rays for Mallex Smith. Fraley missed most of 2017 with a knee injury and then the early part of 2018 with a foot injury after spending the offseason in the Australian Baseball League. Healthy for the second half of 2018, he hit .347/.415/.547 at high Class A Charlotte.

    Scouting Report: Fraley has a good approach at the plate with above-average bat speed and a simple, balanced swing, but his 2018 numbers overstate his impact potential. He has a track record for putting the bat on the ball and drawing walks. While he hits righthanders better, Fraley has shown that he holds his own against southpaws. His below-average power results in more doubles to the gap than balls over the fence. His best tool is his plus speed, allowing him to stay in center field, but he needs to develop better instincts on the bases. Above-average range and a fringe-average arm are enough for all three outfield positions, and his most likely big league role will be as a versatile backup outfielder.

    The Future: Fraley will have to prove that he can stay on the field after battling injuries. The Mariners will move him quickly to try to make up for lost time. His most likely role is as a fourth outfielder.

  13. 13. Braden Bishop | OF
    Braden Bishop
    Born: Aug 22, 1993
    Bats: R Throws: R
    Ht.: 6'1" Wt.: 190
    Drafted: Washington, 2015 (3rd round).
    Signed By: Jeff Sakamoto.
    Minors: .271/.357/.467 | 8 HR | 2 SB | 214 AB

    Track Record: Bishop was athletic enough in high school that he could have played college football as a wide receiver, but he instead chose to stick to baseball at Washington. He continues to receive acclaim for his 4MOM foundation that raises money for Alzheimer's disease in support of his mother. Bishop was progressing well during the first half of 2018 at Double-A Arkansas. Unfortunately, his season ended early when he suffered a broken hand after being hit by a pitch.

    Scouting Report: Bishop added strength and lowered his hands. That allowed him to get more power into his swing, which has helped him drive the baseball more frequently, giving him a chance to hit double-digit home runs while still being an average hitter. Early in the 2018 season, he was struggling to improve his launch angle, but it all came together for him by midseason when he hit .379/.443/.544 in June. Any offense that Bishop provides will come in addition to what he brings to the field and basepaths, because he is a plus runner and plus-plus defender in center field.

    The Future: The Mariners added Bishop to the 40-man roster in November in his first year of eligibility. He will head to Triple-A Tacoma and could reach Seattle in 2019.

  14. 14. Sam Carlson | RHP
    Sam Carlson
    Born: Dec 3, 1998
    Bats: R Throws: R
    Ht.: 6'4" Wt.: 195
    Drafted: HS--Burnsville, Minn., 2017 (2nd round).
    Signed By: Ben Collman.

    Track Record: Carlson had a strong commitment to Florida before the Mariners signed him for an over-slot $2 million in the second round of the 2017 draft. After two short but impressive appearances in Rookie ball in 2017, Carlson was shut down with some minor soreness that did not look to be a long-term issue. Elbow and forearm tenderness kept him off the mound at 2018 spring training, but he began throwing bullpen sessions in early summer before it was determined that he needed Tommy John surgery in July.

    Scouting Report: Carlson has a prototype pitcher's frame with room to add strength. Prior to the injury, he threw a heavy fastball with late action and natural sink up to 96 mph. His above-average mid-80s slider has late action and tilt, complemented by a changeup that flashes plus. With a loose, quick arm, Carlson uses a delivery that is easy and free-flowing.

    The Future: The Mariners hope that Carlson can be throwing bullpens again by late July and are targeting 2020 for a return to game action. He'll still be just 21, but the Mariners will need to speed his development at that point because he will be in his fourth pro season before he receives significant pro mound experience.

  15. 15. Erik Swanson | RHP
    Erik Swanson
    Born: Sep 4, 1993
    Bats: R Throws: R
    Ht.: 6'3" Wt.: 235
    Drafted: Iowa Western JC, 2014 (8th round).
    Signed By: Dustin Smith (Rangers).
    Minors: 0-1 | 5.55 ERA | 28 SO | 12 BB | 24.3 IP

    Track Record: The Mariners acquired Swanson from the Yankees as one of three prospects exchanged for James Paxton. Originally drafted by the Rangers, Swanson transferred from Wabash (Ill.) JC to Iowa Western JC in 2014 and showed enough there to get drafted in the eighth round. He went all the way to Triple-A Round Rock with Texas in 2015 before being dealt to the Yankees for Carlos Beltran at the 2016 trade deadline. After beginning 2018 at high Class A Tampa, he finished the year by starting Game 1 of the International League playoffs for Triple-A Scranton/Wilkes-Barre.

    Scouting Report: Swanson throws a high-spin fastball with extraordinary riding action and carry through the zone at 91-93 mph while touching a tick higher. He couples the pitch with a mid-80s slider and a low-80s changeup. Both secondary pitches project as average offerings with a little bit more refinement. A big reason for his improvement in 2018 was an uptick in fastball command, particularly when throwing the pitch up in the zone. Some scouts are concerned that he won't be able to get the ball to his glove side as often as necessary because of his delivery. His only real hiccup came in the form of an oblique strain that cost him a chunk of time at midseason.

    The Future: Swanson will go to spring training with a chance to crack the Mariners' rotation, and he projects as a No. 5 starter. .Additional Triple-A seasoning is the most likely Opening Day assignment.

  16. 16. Juan Then | RHP
    Juan Then
    Born: Feb 7, 2000
    Bats: R Throws: R
    Ht.: 6'1" Wt.: 155
    Drafted: Signed: Dominican Republic, 2016.
    Signed By: Eddy Toledo (Mariners).
    Minors: 1-5 | 2.98 ERA | 48 SO | 13 BB | 48.3 IP

    Track Record: The Mariners liked Then’s quick arm and projectable frame and signed him out of the Dominican Republic for $77,000 in 2016 before flipping him, along with lefty J.P. Sears, to the Yankees for reliever Nick Rumbelow. He made his Yankees debut in 2018, posting a 2.70 ERA in 11 starts in the Rookie-level Gulf Coast League.

    Scouting Report: Then boasts a three-pitch mix that starts with a low-90s fastball that touches 95 mph. The pitch features running and riding action out of an overhand slot. He backs up his fastball with a 78-82 mph curveball with hard, downward snap. The pitch is inconsistent but projects plus with repetition and development. He also throws a mid-80s change that shows hard sinking action and could be average in the future. There are some concerns about his somewhat straight fastball, which is exacerbated by his lack of size and little remaining projectability.

    The Future: Then has a chance to stick in the rotation as his arsenal develops, but the bullpen is also a possibility. He should pitch at one of the Yankees’ two short-season affiliates in 2019.

  17. 17. Matt Festa | RHP
    Matt Festa
    Born: Mar 11, 1993
    Bats: R Throws: R
    Ht.: 6'2" Wt.: 195
    Drafted: East Stroudsburg (Pa.), 2016 (7th round).
    Signed By: Ross Vecchio.
    Minors: 1-0 | 2.56 ERA | 35 SO | 14 BB | 31.7 IP

    Track Record: Signed for $5,000 after being drafted in the seventh round out of Division II East Stroudsburg, Festa turned out to be first Mariners 2016 draft pick to reach the big leagues. He made eight relief appearances for Seattle in 2018, capping off a rapid ascent. Festa's 2018 season was delayed by a hip flexor issue, but he proved to be effective at Double-A Arkansas.

    Scouting Report: While he has a more diverse mix than most relievers, Festa is at his best when using his 92-94 mph fastball in conjunction with his plus slider. The latter is a harder pitch with glove-side cut that typically sits around 87 mph, and he uses it often as a strikeout pitch against righthanders. He also uses a sinker, most notably against lefthanders, and mixes in a changeup and 12-to-6 curveball in the low 80s, albeit less frequently than the rest of his repertoire. Festa's above-average control is the difference-maker for him. He delivers his pitches with a loose, high three-quarter arm slot that he repeats.

    The Future: After getting a taste of the big leagues in 2018, Festa will go to spring training with a chance to break camp in the Mariners' bullpen. He doesn't have the velocity to profile as a closer but should be effective in high-leverage situations.

  18. 18. Brandon Williamson | LHP
    Brandon Williamson
    Born: Apr 2, 1998
    Bats: L Throws: L
    Ht.: 6'6" Wt.: 210
    Minors: 0-0 | 2.35 ERA | 25 SO | 5 BB | 15.3 IP

    After a solid season at Northern Iowa Area CC in 2018, Williamson fell to the Brewers in the 36th round because no team wanted to match his asking price. So instead of signing, Williamson moved on to Texas Christian, where he immediately stepped into the Horned Frogs’ weekend rotation. There’s a lot to like with Williamson, who pitches from an athletic, 6-foot-5 frame. He’s also shown steady improvement over the past two years, and he has a fluid delivery with a clean arm path. The one thing holding Williamson back is a lack of a clear plus pitch, although his 90-92 mph fastball will touch 94-95 mph at times and has the potential to be an above-average offering. He has both a curveball and a slider that are two distinct pitches, but both are fringe-average to average at best. He also has a fringe-average changeup. Williamson is relatively durable and has some projection remaining. As a reasonably productive lefthanded starter at a major college program, Williamson will likely be picked somewhere between the late second and early fourth round.

  19. 19. Dom Thompson-Williams | OF
    Dom Thompson-Williams
    Born: Apr 21, 1995
    Bats: L Throws: L
    Ht.: 6'0" Wt.: 190
    Drafted: South Carolina, 2016 (5th round).
    Signed By: Billy Godwin (Yankees).
    Minors: .234/.299/.397 | 13 HR | 15 SB | 428 AB

    Track Record: Thompson-Williams' third pro season was his best to date, prompting the Mariners to acquire him as part of a three-prospect return from the Yankees in the James Paxton trade. He was originally drafted by the Yankees in the fifth round in 2016 after his lone season at South Carolina, having played two previous years at Iowa Western JC. Thompson-Williams spent most of 2018 at high Class A Tampa and hit .299/.356/.517 with 22 home runs and 20 stolen bases. He was one of only six minor league players to reach the 20-20 mark in 2018, despite missing a month to a hamstring injury.

    Scouting Report: Thompson-Williams, who will turn 24 early in 2019, may be an example of a raw athlete breaking out later in his career. He has explosive, quick-twitch athleticism, combined with sneaky power to all fields, and has at least average raw power with a chance for more to come. An above-average defender with an average arm, Thompson-Williams can stay in center field but can also handle all three positions in a fourth outfielder role. His run times in 2018 were inconsistent, perhaps due to his hamstring problems, but he's at least an average runner out of the box and a tick better in the field.

    The Future: After a strong season in the Florida State League, Thompson-Williams will head to Double-A Arkansas in 2019 and could see Triple-A by midseason.

  20. 20. Wyatt Mills | RHP
    Wyatt Mills
    Born: Jan 25, 1995
    Bats: R Throws: R
    Ht.: 6'3" Wt.: 175
    Drafted: Gonzaga, 2017 (3rd round).
    Signed By: Alex Ross/Jeff Sakamoto.
    Minors: 4-1 | 4.31 ERA | 68 SO | 17 BB | 54.3 IP

    Track Record: Mills pitched exclusively out of the bullpen in four years at Gonzaga, where he recorded a 1.79 ERA with 12 saves as a senior. Drafted in the third round in 2017 with the intention of moving through the Mariners' system quickly, Mills made it to Double-A Arkansas by the end of his first full season and then spent time in the Arizona Fall League.

    Scouting Report: Pitching from a sidearm slot, Mills gives hitters a different look, with his pitches appearing to come out of his hip. It's a funky, deceptive delivery, but he repeats it well. Mills' typical 88-92 mph fastball has both sink and armside movement, and he showed increased velocity in the AFL, when he sat 94-95 mph. His average 81-84 mph slider has two-plane movement and can be a swing-and-miss pitch, but it currently doesn't have enough tilt and needs to thrown in the zone more often against more advanced hitters. Mills throws his 80-83 mph changeup for strikes, using it more often against lefthanded batters, but he's predominately a fastball/slider reliever.

    The Future: After a successful stint in AFL, Mills should be ready to give Double-A another shot in 2019 and will likely make it to Triple-A before long. He could be pitching in high-leverage situations if he maintains the increased velocity and improves his slider.

  21. 21. Juan Querecuto | SS
    Juan Querecuto
    Born: Sep 21, 2000
    Bats: R Throws: R
    Ht.: 6'2" Wt.: 175
    Drafted: Signed: Venezuela, 2017.
    Signed By: Emilio Carrasquel/Tim Kissner.
    Minors: .203/.315/.241 | 0 HR | 2 SB | 79 AB

    Track Record: Signed by the Mariners in 2017 for $1.225 million, Querecuto spent 2018 playing shortstop in the Dominican Summer League. His high baseball IQ comes naturally because his father Juan played in the Blue Jays' farm system and his brother Juniel played in the Diamondbacks' organization in 2018 after reaching the big leagues with the Rays in 2016.

    Scouting Report: Querecuto is known for his skills more than his tools. He consistently does the little things well with a knack of regularly being in the right spot at the right time. He made strides at the plate in 2018 by better controlling the barrel and using all fields. With good strike-zone awareness, Querecuto is more of a contact, gap-to-gap hitter with current below-average power. He spent the fall at the Mariners' complex in Arizona improving his strength, so there may be more power to come as he physically matures. A below-average runner, Querecuto compensates with instincts and positioning at shortstop, and his plus-plus arm already ranks as the best infield arm in the Mariners' system.

    The Future: Querecuto will make his U.S. debut in the Rookie-level Arizona League in 2019.

  22. 22. Taylor Guilbeau | LHP
    Taylor Guilbeau
    Born: May 12, 1993
    Bats: L Throws: L
    Ht.: 6'4" Wt.: 180
    Minors: 3-2 | 2.77 ERA | 55 SO | 17 BB | 48.7 IP
  23. 23. Brayan Perez | LHP
    Brayan Perez
    Born: Sep 5, 2000
    Bats: L Throws: L
    Ht.: 6'0" Wt.: 170
    Drafted: Signed: Venezuela, 2017.
    Signed By: Tim Kissner.
    Minors: 8-1 | 3.34 ERA | 62 SO | 17 BB | 67.3 IP

    Track Record: The Mariners' 2017 international signing class is beginning to look more interesting, which should add intrigue to the organization's Rookie-level Arizona League affiliate in 2019. Perez, a pitchability Venezuelan lefthander who signed for $350,000, projects as the best pitcher from that signing class. He had an impressive debut in the Dominican Summer League, when he struck out 58 batters in 53 innings while walking just 11.

    Scouting Report: Perez is already known for his advanced feel to pitch. He throws an 85-91 mph fastball with deception, and he is projected to add velocity with added strength and maturity. He throws a slurvy 73-77 mph breaking ball that can look like either a slider or curveball depending on how he adds or subtracts velocity. Regardless, it's his best out pitch and could be a plus offering with further refinement. Perez's changeup is still a work in progress, but he delivers all his pitches from a smooth, easy delivery and a low three-quarters slot.

    The Future: Perez will begin 2019 at the Mariners' complex in Peoria, Ariz., before joining the AZL team.

  24. 24. Aaron Fletcher | LHP
    Aaron Fletcher
    Born: Feb 25, 1996
    Bats: L Throws: L
    Ht.: 6'0" Wt.: 220
    Signed By: Tyler Wilt
    Minors: 5-3 | 2.02 ERA | 82 SO | 16 BB | 71.3 IP
  25. 25. Joe Rizzo | 3B
    Joe Rizzo
    Born: Mar 31, 1998
    Bats: L Throws: R
    Ht.: 5'10" Wt.: 194
    Drafted: HS--Vienna, Va., 2016 (2nd round).
    Signed By: Ross Vecchio.
    Minors: .296/.355/.424 | 10 HR | 0 SB | 514 AB

    Track Record: Drafted out of a Virginia high school in the second round in 2016, Rizzo took a step back in 2018. He hit .241/.303/.321 for high Class A Modesto in the hitter-friendly California League. Rizzo also didn't do much to answer questions about whether he could handle third base.

    Scouting Report: Despite not showing a lot of impact with his bat in 2018, Rizzo still has believers who think he can develop into a serviceable hitter. He's still learning to make adjustments, possesses solid bat-to-ball skills and has outstanding makeup. He shows good raw power, but it has yet to show up in games. The biggest question is where Rizzo fits on the field because he is not very skilled defensively. His tick above-average arm is enough for third base, but he struggles with range to both his right and left. At 5-foot-9, Rizzo is too short for first base, and his below-average speed limits his chances at other positions.

    The Future: Rizzo will return to Modesto in 2019, when he'll be 21 and more age-appropriate for the Cal League. It'll be a key year for Rizzo, who needs to show growth in both his bat and glove.

  26. 26. Joey Gerber | RHP
    Joey Gerber
    Born: May 3, 1997
    Bats: R Throws: R
    Ht.: 6'4" Wt.: 215
    Drafted: Illinois, 2018 (8th round).
    Signed By: Ben Collman.
    Minors: 1-3 | 2.59 ERA | 69 SO | 19 BB | 48.7 IP

    Track Record: A pure reliever with an aggressive delivery, Gerber was a closer at Illinois and averaged just over 12 strikeouts per nine innings during his three years in college. Drafted by the Mariners in the eighth round in 2018, Gerber pitched well at both short-season Everett and at low Class A Clinton in his pro debut, combining for a 2.10 ERA and 15 strikeouts per nine innings.

    Scouting Report: The 6-foot-4 Gerber is an imposing figure on the mound who comes right at hitters with premium velocity. He has what's been called violent velocity--a plus fastball that he throws for strikes from 92-96 mph with movement, life and sink. His fringe-average slider flashed above-average potential, but he needs to make it sharper more consistently. He had a decent changeup in college but rarely used it. Gerber uses a herky-jerky delivery with effort, but he stays online with a quick tempo to keep hitters from getting comfortable in the box.

    The Future: After dominating hitters in low Class A, look for Gerber to start 2019 at high Class A Modesto.

  27. 27. Donnie Walton | 2B
    Donnie Walton
    Born: May 25, 1994
    Bats: B Throws: R
    Ht.: 5'10" Wt.: 184
    Drafted: Oklahoma State, 2016 (5th round).
    Signed By: Ty Bowman.
    Minors: .313/.403/.442 | 11 HR | 10 SB | 473 AB

    Track Record: A four-year starter at Oklahoma State and the son of a coach, Walton is selfless and plays hard. He hit well at high Class A Modesto in 2018 before scuffling at Double-A.

    Scouting Report: Walton is fundamentally strong and has an uncanny ability to slow the game down, with a reputation for pushing his teammates to work harder by example. He has a good approach at the plate and does the little things well, including bunting, advancing runners and taking the extra base. Despite below-average speed, Walton steals bases and is a strong baserunner because of his advanced instincts. He's a capable defender at all infield positions with a tick above-average arm.

    The Future: Walton is future utility infielder with a high likelihood of reaching that ceiling.

  28. 28. Anthony Misiewicz | LHP
    Anthony Misiewicz
    Born: Nov 1, 1994
    Bats: R Throws: L
    Ht.: 6'1" Wt.: 190
    Drafted: Michigan State, 2015 (18th round).
    Signed By: Jay Catalano.
    Minors: 10-8 | 4.39 ERA | 128 SO | 35 BB | 137.3 IP

    Track Record: Used mostly as a reliever in college, Misiewicz has worked primarily in the rotation since turning pro. Traded to the Rays in August 2017, he was reacquired by the Mariners four months later via trade. Misiewicz struggled at Double-A in 2018 but got back on track in the Arizona Fall League.

    Scouting Report: Misiewicz is a gritty, strike-throwing competitor with a four-pitch mix who gets by with finesse more than pure stuff. His fringe-average fastball sits 88-92 mph with some tail, and his 79-81 mph above-average curveball has late angle and sharp, downward action. His 86-88 mph slider is more of a cutter that he throws for strikes. Misiewicz also mixes in a low-80s changeup that showed improvement in the AFL. He repeats his high three-quarters arm slot well, but it doesn't provide a lot of deception.

    The Future: Misiewicz doesn't have a record of pitching deep into his starts, and he is generally more effective in shorter stints, marking him as a likely relief candidate.

  29. 29. Nolan Hoffman | RHP
    Nolan Hoffman
    Born: Aug 9, 1997
    Bats: R Throws: R
    Ht.: 6'4" Wt.: 190
    Drafted: Texas A&M, 2018 (5th round).
    Signed By: Austin Wates.
    Minors: 0-1 | 1.08 ERA | 7 SO | 4 BB | 8.3 IP

    Track Record: After spending two seasons at Hutchinson (Kan.) JC, Hutchinson went to Texas A&M. He posted a 1.24 ERA in 32 relief appearances in 2018, then signed for $300,000 after being drafted by the Mariners in the fifth round. He started his pro career with six short appearances in the Rookie-level Arizona League. In July, Hoffman was promoted to short-season Everett, where he posted a 2.45 ERA.

    Scouting Report: Hoffman could be considered the next version of fellow Mariners righthander Wyatt Mills, because he delivers pitches from a low arm slot. Hoffman pitches from an even lower slot than Mills, using submarine depth while drawing comparisons with major league reliever Darren O'Day. His upper-80s to low-90s fastball is an average pitch that comes across the plate heavy with late, plus sink. His fastball plays up because he locates it to both sides of the plate, while his fringe-average slider has whip and three-quarter tilt. He has below-average stuff now with plus movement and projected plus command.

    The Future: Like Mills, Hoffman has enough stuff, command and deception to move quickly. If he doesn't skip a level and start the 2019 season at high Class A Modesto, then he should get there before the end of the year. An uptick in velocity and improvement in his breaking ball would help solidify his projection as a solid middle reliever.

  30. 30. Jose Caballero | 2B
    Jose Caballero
    Born: Aug 30, 1996
    Bats: R Throws: R
    Ht.: 5'10" Wt.: 185
    Minors: .272/.375/.385 | 3 HR | 33 SB | 265 AB
View Players 11-30

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