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2017 Seattle Mariners Midseason Top 10 Prospects

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Mariners Midseason Top 10
1. Kyle Lewis, OF
2. Nick Neidert, RHP
3. Tyler O’Neill, OF
4. Andrew Moore, RHP
5. Evan White, 1B
6. Sam Carlson, RHP
7. Braden Bishop, OF
8. Thyago Vieira, RHP
9. Max Povse, RHP
10. Alexander Campos, SS
The Mariners had the busiest offseason of any team in baseball, making 15 trades in an attempt to push the franchise to its first playoff appearance since 2001.

While they haven’t exactly set the world on fire, they are in wild-card contention and making more moves to try and get over the top. The Mariners have spent the year stuck hovering around .500—they’ve had a winning record for all of three days this entire season—but nonetheless entered July 20 just 1 1/2 games out of a playoff spot with the rest of the American League wild card field mired in mediocrity.

They already showed themselves to be buyers with a deal to acquire David Phelps from the Marlins for four prospects, and more moves are in play.

Mitch Haniger, Felix Hernandez, Robinson Cano and Jean Segura are all finally healthy together after spending time on the DL at various points, and as a result the Mariners are playing their best baseball of the season. They have won seven of nine to pull back to .500, and still stand to get Hisashi Iwakuma back from shoulder inflammation later in the year.

Though their core of Hernandez, Iwakuma, Robinson Cano and Nelson Cruz is getting older, the Mariners have shown no indication they are going to tear down. With the longest current playoff drought in baseball hanging over them (since 2001), they are going for it and making the most of what they can with a limited farm system.

1. Kyle Lewis, OF High Class A Modesto Age: 21

Lewis spent 11 months recovering from a torn ACL and finally made his 2017 season debut on June 11 with high Class A Modesto. Unfortunately, it was short-lived. Lewis banged into the wall in center field his first game back and was pulled, got three at-bats the next day as the DH and was subsequently placed on the disabled list with bruising and soreness in his surgically-repaired right knee. He just finished his rehab assignment and returned to Modesto on Thursday. Even though Lewis’ growing injury track record is concerning, he remains the best package of tools and ability in the system.

2. Nick Neidert, RHP Double-A Arkansas Age: 20

Neidert continues to get stronger and improve his velocity while keeping his exceptional command and feel for pitching. The Mariners challenged Neidert to strike more people out this season and he has done just that, recording 109 strikeouts against just 17 walks in 104.1 innings while going 10-3, 2.76 in high Class A before earning a promotion to Double-A.

3. Tyler O’Neill, OF Triple-A Tacoma Age: 22

The steepness of O’Neill’s swing path caught up to him in Triple-A, where advanced pitchers took advantage of O’Neill’s bat head not being in the zone very long and his penchant for chasing sliders. O’Neill began to adjust with 11 home runs in a 23-game stretch starting in late June, a promising development in his attempt to turn his season around.

4. Andrew Moore, RHP Seattle Age: 23

Moore’s rapid rise continued as soon as the season commenced. He was promoted to Triple-A Tacoma quickly, excelled there with elevated fastballs and an improved slider, and made his major league debut June 23. Moore’s pure stuff remains largely average, but his supreme command and tempo keeps hitters on the defensive.

5. Evan White, 1B Short-season Everett Age: 21

The Mariners picked White No. 17 overall out of Kentucky in June and consider him their first baseman of the future. He was one of the most defensively-gifted first basemen to come through the draft in years, and he matches his Gold Glove potential with a line-drive stroke geared for a high average, emerging power and plus speed.

6. Sam Carlson, RHP Rookie-level Arizona Age: 18

Evaluators largely considered Carlson the best Minnesota prep prospect since Joe Mauer, and the Mariners drafted him No. 55 overall and signed him for $2 million. Carlson has the best potential stuff of any pitcher in the system with a 91-95 mph fastball, a devastating changeup and an improving slider, but many years of development remain ahead.

7. Braden Bishop, OF High Class A Modesto Age: 23

Bishop lowered his hands in his stance during in an effort to flatten out his swing and get the ball in the air more. The change worked. Bishop is now driving the ball to all fields, has already set new career-highs in doubles and triples, and is on pace for new bests in on-base percentage and slugging percentage.

8. Thyago Vieira, RHP Triple-A Tacoma Age: 24

Vieira is still lighting up radar guns with 101 mph fastballs, and his control is recovering after a rough big league camp and rocky start to the season. He allowed just five earned runs in his final two months at Double-A and was promoted to Tacoma earlier this week.

9. Max Povse, RHP Seattle Age: 23

Povse jumped straight from Double-A to the majors and made his MLB debut on June 22 out of the bullpen. He has gotten stronger and more coordinated in his 6-foot-8 frame and increased his fastball velocity to 94-95 mph from the low 90s, an important development now that the Mariners are considering him for a long reliever role.

10. Alexander Campos, SS Rookie-level DSL Mariners Age: 17

Campos was one of the Mariners' top international signings in 2016 and is showing the tools to be a future everyday shortstop in his first professional season. He has progressed quickly from the time he signed and is showing the potential for plus defense and a plus arm at short with a strong, line-drive stroke and plus run times.


• OF Ian Miller spent the offseason reworking his swing with hitting coordinator Brant Brown and was leading the Double-A Texas League with a .325 batting average. His 70-grade speed and superb baserunning instincts have yielded 30 stolen bases in 34 attempts.

• RHP Matt Festa is sitting 94-96 mph with his lively fastball and is blowing hitters away in relief at high Class A Modesto.

• LHP JP Sears, the Mariners' 11th-round pick in June, finished fifth in the nation strikeouts this year at The Citadel and was 1-1, 1.67 with 22 strikeouts and three walks in 10.2 innings at short-season Everett.

• RHP Juan Then, a 17-year-old Dominican signed last year, has filled out and seen his velocity jump from 84-88 mph to 90-94 mph. He is showing plus control and the makings of a future plus changeup and above-average breaking ball.


• 1B Dan Vogelbach failed to win the starting first base job out of camp and did not impress during a May callup. Few believe his bat contains enough impact to overcome his bottom-of-the-scale defense.

• The statistics don't always tell the tale, but they've been poor offensively and defensively for low Class A Clinton 3B Joe Rizzo. Evaluators have been scathing in their reviews, citing poor athleticism, an inability to play third base and less hitting ability and power than was advertised prior to the 2016 draft, when Rizzo was a second-rounder.

• 1B D.J. Peterson’s ability to control the strike zone has not improved, and thus he has a .265 average and .740 OPS at Triple-A as a 25-year-old.


• SS Chris Torres was sidelined with tenderness in his left (non-throwing) shoulder during the spring but reported to Everett at the end of June

• SS Donnie Walton had surgery to repair a broken bone in his hand and will be out until August.


• OF Mitch Haniger won the Opening Day job in right field and hit .273 with seven homers, 23 RBIs and an .847 OPS in the first half.

• RHPs Dan Altavilla and Tony Zych and LHP James Pazos have settled into the bullpen.

• OFs Ben Gamel and Guillermo Heredia took advantage of injuries to expected starters and became key components of the Mariners outfield rotation.

• IF/OF Taylor Motter has taken over the primary utilityman role.


Sam Carlson Makes First Start Since 2017

The 22-year-old righthander did not miss a beat in his first few starts in his return from Tommy John surgery.

• RHP Sam Gaviglio joined the Mariners after injuries struck and proved serviceable at the back end of the rotation, going 3-5, 4.62

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