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Arizona Diamondbacks

Prospects Overview

Top 10 Prospects

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Player Reports

  1. 1. Daulton Varsho | C
    Daulton Varsho
    Born: Jul 2, 1996
    Bats: L Throws: R
    Ht.: 5'10" Wt.: 190
    Drafted: Wisconsin-Milwaukee, 2017 (2nd round supplemental).
    Signed By: Rick Short.

    BA Grade: 55. Risk: Medium
    Tool Grades: Hit: 55. Power: 50. Run: 55. Fielding: 50. Arm: 45.

    Track Record: Varsho, the son of ex-big leaguer Gary Varsho, cemented his status as one of the Diamondbacks’ most dynamic prospects last year when he put together one of the better seasons of any hitter at Double-A. In leading the Southern League in OPS, Varsho showed an ability to hit for average and get on base, displayed both power and speed and played well at two positions high on the defensive spectrum. Though he finally began to gain industry-wide recognition in 2019, his production generally fell in line with what he had done throughout his career.

    Scouting Report: With short arms and a compact swing, Varsho finds the barrel often. He has a mature approach and will take his walks, and he also has good hand-eye skills that allow him to spray the ball to all fields. His power potential generates mixed feelings, with some scouts anticipating 20-plus home runs while others see him merely reaching double digits. He has above-average speed (and not just for a catcher) and is a good baserunner; he became the first backstop at Double-A or Triple-A to steal 20-plus bases since at least 2006. He even runs well enough to hold his own in center field, which he did during a cameo there over the final two weeks of the season. Scouts and executives both inside and outside the organization believe he can be at least an average defensive major league catcher. He is athletic, a decent receiver, blocks well and compensates for below-average arm strength with a quick transfer that leads to at least average times on throws to second base. D-backs officials were encouraged by Varsho’s brief exposure to center field, which came as no surprise given the high marks he receives for his baseball instincts.

    The Future: With catcher Carson Kelly’s emergence as a potential frontline catcher, the D-backs started to experiment with other paths toward big league at-bats for Varsho in August. His outfield experience was limited to center field, but club officials say he also could be exposed to left field and did not rule out the possibility of second base. Despite Varsho’s athleticism, speed and track record, some evaluators are cautious in projecting him as more than a solid-average everyday player because they do not see a carrying tool. Others, however, see a versatile impact player with relatively few historical comparisons. Varsho is likely to open the year in Triple-A Reno and should give the D-backs the kind of flexibility their front office values.

  2. 2. Geraldo Perdomo | SS
    Geraldo Perdomo
    Born: Oct 22, 1999
    Bats: B Throws: R
    Ht.: 6'3" Wt.: 184
    Drafted: Signed: Dominican Republic, 2016.
    Signed By: Junior Noboa/Elvis Cruz.

    BA Grade: 55. Risk: High
    Tool Grades: Hit: 55. Power: 45. Run: 55. Fielding: 60. Arm: 60.

    Track Record: Following the trade deadline deal that sent Jazz Chisholm to the Marlins, Perdomo took the reins as the D-backs’ shortstop of the future. His play earned him such a designation in 2019, a year in which he reached high Class A and put together a solid six weeks in the Arizona Fall League.



    Scouting Report: The switch-hitting Perdomo is best known for his mature approach and on-base ability and stayed true to form by finishing last year with more walks than strikeouts. He has good bat speed and bat-to-ball ability, and scouts who watched him in the AFL saw him unload on a handful of balls, giving them reason to dream on potentially average power. Perdomo is an above-average runner whose speed plays up thanks to his instincts. He is a graceful defender with good range, a plus arm and an accurate internal clock. He is a consistent and dependable defender whom scouts have little doubt will stick at short.

    The Future: Given his defense, speed and approach, Perdomo is on his way toward being an above-average everyday player. He grew an inch taller from 2018 to 2019 and still has plenty of maturing to do physically. If that leads to more pop, the D-backs could have an all-star.

  3. 3. Kristian Robinson | OF
    Kristian Robinson
    Born: Dec 11, 2000
    Bats: R Throws: R
    Ht.: 6'3" Wt.: 190
    Drafted: Signed: Bahamas, 2017.
    Signed By: Cesar Geronimo/Craig Shipley.

    BA Grade: 60. Risk: Very High
    Tool Grades: Hit: 50. Power: 70. Run: 60. Fielding: 55. Arm: 50. v Track Record: Robinson received a $2.5 million bonus in 2017 and put his massive skill set on display in the short-season Northwest League in 2019, dominating against much older competition. Playing the entire season at age 18, he reached low Class A for the final month of the season.

    Scouting Report: A physical specimen despite his age, Robinson has a chance for four plus tools, the exception being his arm. At the plate, he uses a simple stride with little movement in his setup followed by a compact swing. The raw power he generates is enormous, and he got to it often in games last season. Scouts are concerned by his strikeout total, but his chase rate is solid and his in-zone whiff rate isn’t bad, either. He makes enough hard contact to offset the swing-and-miss in his game. Robinson gets good reads in center field, but scouts expect he will move to a corner position once he fills out. He is mature for his age, a hard worker and routine-oriented. He has plus speed and stole bases at an 82 percent clip in Hillsboro.

    The Future: Given his loud tools, Robinson arguably has more potential than any player in the D-backs system. If he continues his upward trajectory, he could find himself among baseball’s top prospects in short order.

  4. 4. Alek Thomas | OF
    Alek Thomas
    Born: Apr 28, 2000
    Bats: L Throws: L
    Ht.: 5'11" Wt.: 175
    Drafted: HS--Chicago, 2018 (2nd round).
    Signed By: Nate Birtwell.

    BA Grade: 55. Risk: High
    Tool Grades: Hit: 60. Power: 45. Run: 60. Fielding: 60. Arm: 45

    Track Record: Thomas, the son of White Sox strength coach Allen Thomas, performed well in the low Class A Midwest League in his first full season as a pro and mostly held his own at high Class A Visalia after an August promotion. Fast, instinctual and with a nose for hitting, Thomas capped his season with a walk-off RBI double to give Visalia the California League championship.

    Scouting Report: Thomas has a lot of moving parts with his swing, including a big leg kick and active hands before he loads. But he consistently manages to be in the right position and on time when he swings, and he is able to generate hard line drives on all types of pitches. He has an aggressive approach that will lead to strikeouts, but he will also take a walk. Thomas surprises with the power he generates from his undersized frame, but how that will translate in the majors remains a question among scouts, most of whom project 12-15 home run totals. He is a plus runner who could steal 20-plus bases. Thomas gets good reads and will have no trouble sticking in center field. His arm is improving but remains below-average.

    The Future: Scouts love the way Thomas plays and compare him with Adam Eaton and Jon Jay.

  5. 5. Corbin Carroll | OF
    Corbin Carroll
    Born: Aug 21, 2000
    Bats: L Throws: L
    Ht.: 5'10" Wt.: 165
    Drafted: Drafted: HS—Seattle, 2019 (1st round).
    Signed By: Dan Ramsay.

    BA Grade: 55. Risk: Very High
    Tool Grades: Hit: 55. Power: 45. Run: 70. Fielding: 60. Arm: 45.

    Track Record: The D-backs’ front office hasn’t shied away from taking undersized position players high in the draft the past few years, and the 5-foot-10 Carroll became the latest such selection. The club was thrilled a player it had rated in the top 10 of the draft made it to No. 16 overall. Carroll signed for $3.75 million, forgoing his commitment to UCLA.

    Scouting Report: Carroll, whose game is similar to fellow D-backs prospect Alek Thomas, described his play as “tools meets gamer.” Scouts and coaches paint a similar picture. Carroll has a fluid swing with which he sprays line drives to all fields. He has surprising average raw power, which he put on display during an impressive batting practice session at Chase Field after he signed. In his pro debut in the Rookie-level Arizona League and short-season Northwest League, he showed some swing-and-miss tendencies but also carried an impressive 15.5 percent walk rate. Carroll is a burner whose plus-plus speed plays on the bases and in center field, where he projects to be a plus defender. He has an accurate but below-average arm. An advanced player for his age, he has good instincts and good baseball acumen.

    The Future: Carroll will look to build on his strong pro debut in 2020, beginning at low Class A Kane County.

  6. 6. Blake Walston | LHP
    Blake Walston
    Born: Jun 28, 2001
    Bats: L Throws: L
    Ht.: 6'5" Wt.: 175
    Drafted: Drafted: HS—Wilmington, N.C., 2019 (1st round).
    Signed By: George Swain.

    BA Grade: 55. Risk: Extreme
    Tool Grades: Fastball: 60. Curveball: 60. Slider: 50. Changeup: 50. Control: 55.

    Track Record: The D-backs saw a projectable lefthander with plenty of stuff to dream on in Walston and surprised many, including Walston himself, when they selected him 26th overall in the 2019 draft. He signed for $2.45 million to forgo a North Carolina State commitment. Walston made huge strides in his first summer as a pro, adding both strength and velocity.

    Scouting Report: In the world of high school pitchers, Walston checks all the boxes when it comes to projectability. He’s tall and lanky with room to add strength; he has a clean arm action and delivery; he showed velocity and the ability to spin a breaking ball; and he is an excellent athlete, evidenced by his success as a high school quarterback. While his velocity fluctuated during the spring, he was more consistent after signing, regularly touching 96-97 mph. His plus curveball and average slider tended to bleed together, and some feel he could benefit from settling on one or the other. His changeup is lightly used but showed flashes of being an average pitch.

    The Future: Walston excited the Diamondbacks with glimpses of his potential last summer, drawing comparisons to a young Barry Zito. He likely will open the season in extended spring training with a chance to push his way to low Class A Kane County.

  7. 7. Liover Peguero | SS
    Liover Peguero
    Born: Dec 31, 2000
    Bats: R Throws: R
    Ht.: 6'1" Wt.: 160
    Drafted: Signed: Dominican Republic, 2017.
    Signed By: Cesar Geronimo.

    BA Grade: 55. Risk: Extreme
    Tool Grades: Hit: 55. Power: 50. Run: 55. Fielding: 55. Arm: 55.

    Track Record: When Latin American scouting director Cesar Geronimo first saw Peguero, he was a skinny, 5-foot-10 teenager who managed to hit the ball as hard as any of the bigger players around him. Peguero is still lean, but he’s grown at least four inches and added at least 30 pounds since the club invested $475,000 in him. He starred at Rookie-level Missoula in his U.S. debut and finished at short-season Hillsboro.

    Scouting Report: Regarded as a premium athlete, Peguero has a strong, wiry build and above-average speed. He has a feel for finding the barrel and regularly generates loud contact. With a body that still has room to fill out, his average power projection could continue to grow. Peguero’s approach is aggressive, but he showed signs last year of being more selective. He won over skeptical coaches and evaluators with his improved defense last season, leading many to change their minds about his ability to stick at shortstop. If he does have to move, he could easily fit elsewhere on the infield or even in center field, where his long strides would cover a lot of ground.

    The Future: Peguero has a ways to go, but his offensive-minded profile brings to mind a longer and leaner Jean Segura. He should make the jump to full-season ball in 2020.

  8. 8. Corbin Martin | RHP
    Corbin Martin
    Born: Dec 28, 1995
    Bats: R Throws: R
    Ht.: 6'2" Wt.: 200
    Drafted: Texas A&M, 2017 (2nd round).
    Signed By: Noel Gonzales-Luna. (HOU)

    BA Grade: 50. Risk: High
    Tool Grades: Fastball: 60. Curveball: 55. Slider: 50. Changeup: 50. Control: 55.

    Track Record: Martin reached the majors last season and made five starts for the Astros before being sent back to Triple-A Round Rock in June. Three starts later, he went down with elbow problems that ultimately required Tommy John surgery. The injury will sideline him for most, if not all, of the 2020 season, but it didn’t deter the D-backs from acquiring him as part of the four-player package for righthander Zack Greinke at the 2019 trade deadline.

    Scouting Report: The surgery will act as a bumper on what had been a fast-track career for Martin, who reached the big leagues less than two years after being drafted. He is a good athlete with clean arm action and a simple, repeatable delivery. Assuming he can get back to what he was, Martin will give the D-backs a polished starter with a four-pitch mix. His fastball sits in the 94-95 mph range, touching 98, and he commands it well to both sides of the plate. His slider and curveball both can be above-average pitches. His slider is more consistent, but when it’s on his curveball can be better. His changeup comes in firm but with good armside run.

    The Future: If all goes well, Martin will return to game action after the all-star break.

  9. 9. Brennan Malone | RHP
    Brennan Malone
    Born: Sep 8, 2000
    Bats: R Throws: R
    Ht.: 6'4" Wt.: 205
    Drafted: Drafted: HS—Bradenton, Fla., 2019 (1st round).
    Signed By: Matt Mercurio.

    BA Grade: 55. Risk: Extreme
    Tool Grades: Fastball: 60. Curveball: 50. Slider: 60. Changeup: 50. Control: 50.

    Track Record: Long regarded as one of the top prep arms in the 2019 class, Malone solidified his stock with a strong spring at IMG Academy, where the North Carolina native transferred for his senior year. The D-backs used the third of their seven first-day draft picks on Malone, taking him 33rd overall and signing him for $2.2 million to forgo a North Carolina commitment.

    Scouting Report: Malone featured perhaps the best combination of present stuff and future projection of any high school pitcher in his class. He has a strong, durable frame and an athletic delivery with a loose, easy arm action. He showed plus fastball velocity consistently throughout the spring, sitting 93 mph while touching the upper 90s. His slider is his best secondary offering, a potential plus pitch with sharp, late break that he throws at the back foot of lefthanded hitters. His curveball and changeup are less consistent, but both project average. Malone has a mature, stoic demeanor on the mound. At times, his command deserts him and he can look more like a thrower than a pitcher.

    The Future: Malone has the ingredients to become a power starter, with his upside to be determined by how his command and stuff progress.

  10. 10. Luis Frias | RHP
    Luis Frias
    Born: May 23, 1998
    Bats: R Throws: R
    Ht.: 6'3" Wt.: 180
    Drafted: Signed: Dominican Republic, 2015.
    Signed By: Jose Ortiz/Junior Noboa.

    BA Grade: 55. Risk: Extreme
    Tool Grades: Fastball: 70. Curveball: 60. Changeup: 50. Control: 50.

    Track Record: Since signing for $50,000 in November 2015, Frias has added size, strength and stuff to develop into one of the more intriguing pitching prospects in the organization. He took steps forward in 2019 by smoothing out his delivery and both refining and adding to his pitch mix, and as a result he reached full-season ball for the first time with low Class A Kane County.

    Scouting Report: Frias comes with some reliever risk, but he has the ingredients of a frontline starter. He has a big, physical build, a fastball that reaches the upper 90s and a swing-and-miss breaking ball. He implemented a spike curveball grip in 2019 that made the pitch a plus offering and turned his changeup into more of a splitter, giving him a usable, average third pitch. Frias ironed out his delivery and began to shed his reputation for being erratic. He also kept his weight in check, staying around the mid-230s after ballooning to more than 250 pounds a year ago.

    The Future: Frias showed progress in 2019, but he will need to continue to refine his arsenal and show his command and control will play against more advanced hitters. He could be a force in the rotation if it all clicks. Otherwise, his path might lead him to a high-leverage relief role.

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