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Seattle Mariners Top 10 Prospects

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1. Alex Jackson, of
2. Edwin Diaz, rhp
3. Drew Jackson, ss
4. Tyler O'Neill, of
5. Nick Neidert, rhp
6. Luiz Gohara, lhp
7. Braden Bishop, of
8. Andrew Moore, rhp
9. Boog Powell, of
10. D.J. Peterson, 1b/3b
The Blue Jays and Mariners came into the major leagues together in 1977 as expansion brethren. They were linked together again this year because when Toronto reached the postseason, it left Seattle with the game’s longest postseason drought. That absence, since the club’s record-setting 116-win season in 2001, has made the Mariners grow fonder for free agent fixes, and the signings of Robinson Cano in 2014 and Nelson Cruz for 2015 were supposed to help push Seattle back to the top of the American League West. Cruz hit 44 homers in a boffo first season at Safeco Field. Cano started poorly but rallied to post a season that would look good on the back of any baseball card, and stalwarts such as ace Felix Hernandez and third baseman Kyle Seager continued their steady excellence. But general manager Jack Zduriencik, in his seventh season, never surrounded those stars with strong complementary talent. So Seattle posted a losing record for the fifth time in his tenure, bringing that tenure to an end and prompting an overhaul of the front office. Jerry Dipoto, who began the season as GM of the rival Angels before he resigned at the end of June, was named to the same post in Seattle in late September. Soon thereafter, he fired manager Lloyd McClendon and brought in his former assistant GM from the Angels, Scott Servais, to manage the Mariners. Dipoto also imported former Rockies coach Andy McKay as his farm director and promoted Tom Allison from pro scouting director to overseeing both the pro and amateur scouting departments. While scouting director Tom McNamara was retained, the Mariners simply must draft better. They finally gave up on 2009 No. 2 overall pick Dustin Ackley, trading him to the Yankees after his bat failed to emerge. They sent 2012 first-rounder Mike Zunino, drafted third overall, to the minors in 2015. Lefty Danny Hultzen, the No. 2 overall pick in a loaded 2011 draft, never has stayed healthy and was removed from the 40-man roster in November. Early returns on first-rounders D.J. Peterson (2013) and Alex Jackson (2014) have been mixed. Dipoto already has reshaped the big league club with eight trades in his first few months on the job. Notably, he has acquired starters (righty Nathan Karns, lefty Wade Miley) and bullpen pieces (righty Joaquin Benoit and lefty C.J. Riefenhauser), middle defenders (outfielders Leonys Martin and Boog Powell, shortstop Luis Sardinas and catcher Steve Clevenger) and a middle-of-the-order bat (Adam Lind). Dipoto also signed closer Steve Cishek, catcher Chris Iannetta and outfielder Nori Aoki, executing all his moves on a budget and with a barren farm system that is leaning heavily on an encouraging 2015 draft class. Seattle looks better equipped to contend and to take advantage of the window of opportunity that still remains cracked due to the brilliance of Cano, Cruz, Hernandez and Seager. Last Year's Mariners Top 10 Prospects
1. Alex Jackson, of
SCOUTING GRADES Batting: 50 Power: 70 Speed: 45 Defense: 50 Arm: 60 Based on 20-80 scouting scale—where 50 represents major league average—and future projection rather than present tools.
Born: Dec. 25, 1995. B-T: R-R. Ht.: 6-2. Wt.: 215. Drafted: HS—San Diego, 2014 (1st round). Signed by: Gary Patchett.
Year Player, Pos. 2015 Org.
2006 Jeff Clement, c Did not play
2007 Adam Jones, of Orioles
2008 Jeff Clement, c Did not play
2009 Greg Halman, of Deceased
2010 Dustin Ackley, of/1b Yankees
2011 Dustin Ackley, 2b Yankees
2012 Taijuan Walker, rhp Mariners
2013 Mike Zunino, c Mariners
2014 Taijuan Walker, rhp Mariners
2015 Alex Jackson, of Mariners
Background: Jackson hit most everything in high school—except a slump. He belted 17 home runs as a sophomore and finished his career with 47 at famed Rancho Bernardo High in San Diego, becoming a three-time BA High School All-American. Jackson won the BA High School Player of the Year award in 2014 and was the premier prep batter in his draft class. He slipped to the Mariners at No. 6 overall only because of the wealth of arms ahead of him. He signed for $4.2 million, shifted from catcher to the outfield and ranked as the No. 1 prospect in the Rookie-level Arizona League. That history of success made Jackson’s lackluster first full season in 2015 all the more puzzling. Perhaps it was the combination of a nagging shoulder injury, an aggressive assignment to low Class A Clinton and his first experience playing in cold weather that led to a poor showing with—which included an 8-for-53 stretch before he was sent to extended spring training in May. Jackson worked on getting back to basics in Arizona, including controlling the strike zone and getting his bat-to-ball skills in better sync, before returning to the field at short-season Everett. He showed more flashes of the above-average bat—including finishing tied for fifth in the Northwest League with eight home runs—but finished with a .239 average. Scouting Report: Despite Jackson’s up-and-down full-season debut, the Mariners have to hope there is no reason for alarm. The tool set that made Jackson a prep sensation remains intact, and it may very well be a matter of him putting the pieces together with a fresh start in 2016. Jackson combines tremendous bat speed and hand-eye coordination with strength to produce a thunderous swing. At his best, he is an advanced hitter who uses a disciplined approach to wait for his pitch and then punish it. He has above-average power to his pull side, and by the end of the season began to show the ability to drive the ball to all fields. He got out of sync in the Midwest League by being overly aggressive and chasing pitcher’s pitches out of the strike zone early in the count. Jackson was noted for a tremendous work ethic in high school, and he has used that to make an easy transition from behind home plate to right field. He has plenty of arm strength and uses his natural athleticism and instincts to take good routes on flyballs. Some observers believe that Jackson often took his first experience with failure into the field with him, sometimes showing a lack of interest or desire. Others believe it’s the same casual style that he has used in a game that has come easy to him most of his life, and that only the results were different this year. Jackson is a below-average runner but doesn’t clog the bases. The Future: Jackson will get a shot to prove 2015 was merely a bump on his road to Seattle when he returns to low Class A at the start of 2016. He has middle-of-the-order potential but needs to show he can make the adjustments to reach it and help turn around the Mariners system.
2015 Club (Class) AVG OBP SLG AB R H 2B 3B HR RBI BB SO SB
Clinton (Lo A) .157 .240 .213 108 10 17 6 0 0 13 6 35 1
Everett (SS) .239 .365 .466 163 31 39 11 1 8 25 21 61 2

2. Edwin Diaz, rhp Born: March 22, 1994. B-T: R-R. Ht.: 6-3. Wt.: 165. Drafted: HS—Caguas, P.R., 2012 (3rd round). Signed by: Noel Sevilla. Background: Diaz has added weight and velocity since signing for $300,000 as a sixth-rounder out of Puerto Rico in 2012. A stronger lower half, better balance and an improved slider keyed his development in 2015, which started with seven strong starts at high Class A Bakersfield and ended with a promotion to Double-A Jackson and Mariners minor league pitcher of the year honors. Scouting Report: Developing feel for his plus, mid-80s slider with tight rotation has proven to be an effective counter to his plus fastball that sits at 93-95 mph and tops out at 98. Toss in a below-average changeup that he’s starting to master but lacks confidence in and Diaz has emerged as a promising—though inconsistent—pitcher. He was at his best in a July 23 outing against Montgomery, when he struck out seven consecutive batters (one shy of matching a Southern League record). He throws strikes but still struggles to command pitches within the zone while learning that he can’t rely on overpowering hitters as he moves up the minor league ladder. When he misses, he tends to leave the ball over the plate. The Future: Diaz’s level-by-level rise will continue at Triple-A Tacoma in 2016, when he will be just 22. Further improvement of his command gives him No. 3 starter potential.
2015 Club (Class) W L ERA G GS CG SV IP H HR BB SO AVG
Bakersfield (Hi A) 2 0 1.70 7 7 0 0 37 21 3 9 42 .167
Jackson (AA) 5 10 4.57 20 20 0 0 104 102 5 37 103 .259

3. Drew Jackson, ss Born: July 28, 1993. B-T: R-R. Ht.: 6-2. Wt: 200. Drafted: Stanford, 2015 (5th round). Signed by: Stacey Pettis.
Year Player, Pos. 2015 Org.
2006 Brandon Morrow, rhp Padres
2007 Phillippe Aumont, rhp Blue Jays
2008 Josh Fields, rhp Astros
2009 Dustin Ackley, of Yankees
2010 Taijuan Walker, rhp (1st round supp.) Mariners
2011 Danny Hultzen, lhp Mariners
2012 Mike Zunino, c Mariners
2013 D.J. Peterson, 3b Mariners
2014 Alex Jackson, of Mariners
2015 Nick Neidert, rhp (second round) Mariners
Background: Jackson turned down the Giants in the 37th round of the 2012 draft to attend Stanford. The younger brother of former Cubs outfielder Brett Jackson, Drew had long tantalized observers with tools but showed little feel to hit during his first two years with the Cardinal, including an uninspiring turn in the Cape Cod League. He missed the first 15 games of his junior season with a hand injury before hitting .320 and signing with the Mariners as a fifth-round pick for $335,400. Scouting Report: Jackson carried his hot streak through his pro debut at short-season Everett, with new contact lenses being a key to his turnaround. He worked with hitting coach Brian Hunter on shortening his swing and keeping the ball out of the air to better take advantage of his double-plus speed. Jackson earned Northwest League MVP honors while leading the league with a .358 average and 47 stolen bases. He’s a top-of-the-order hitter with gap power. Jackson is a steady defender at shortstop with soft hands, average range and a double-plus arm. He sometimes relies on his strong arm too much instead of charging the ball and needs to improve his footwork on throws. He’s an aggressive basestealer with first-step quickness and a knack for reading pitchers. The Future: Jackson could be a disruptive force at the top of the lineup and will make his full-season debut in 2016, possibly at high Class A Bakersfield.
2015 Club (Class) AVG OBP SLG AB R H 2B 3B HR RBI BB SO SB
Everett (SS) .358 .432 .447 226 64 81 12 1 2 26 30 35 47

4. Tyler O’Neill, of Born: June 22, 1995. B-T: R-R. Ht.: 5-11. Wt.: 210. Drafted: HS—Maple Ridge, B.C., 2013 (3rd round). Signed by: Wayne Norton. Video Background: Over the first three months of 2015, O’Neill did little to live down his reputation as a free swinger with premium bat speed who never met a breaking pitch that he wouldn’t take a hack at. He left to play for host Canada in the Pan Am Games in early July after hitting .238 at high Class A Bakersfield. O’Neill hit three homers in the tournament, including a decisive three-run blast against Cuba, to help the Canadians win gold, then took off upon returning to Bakersfield on July 23. Scouting Report: In his final 41 California League games, O’Neill hit .298/.381/.702 with 16 homers to finish with 32, which tied for second-most in the minors. He has plus raw power, so balls disappear over the outfield fence when he makes contact. That qualifier, however, has been his downfall, for he struck out nearly 31 percent of the time in 2015. O’Neill recognizes breaking pitches but has struggled to lay off them. He did a better job later in 2015 after tweaking his stance to better incorporate his lower half. He’s equally aggressive in the field, where his above-average arm strength plays in right field. O’Neill is a raw defender but has improved his routes and instincts. He runs well enough to play center field sporadically and has become a threat on the bases. The Future: Further maturity could make O’Neill a middle-of-the-order threat. He’ll be tested at Double-A Jackson in 2016.
2015 Club (Class) AVG OBP SLG AB R H 2B 3B HR RBI BB SO SB
Bakersfield (Hi A) .260 .316 .558 407 68 106 21 2 32 87 29 137 16

5. Nick Neidert, rhp Born: Nov. 20, 1996. B-T: R-R. Ht.: 6-1. Wt.: 180. Drafted: HS—Suwanee, Ga., 2015 (2nd round). Signed by: Dustin Evans. Video
Danny Hultzen, 2009 $6,350,000
Dustin Ackley, 2011 $6,000,000
Ichiro Suzuki, 2000 $5,000,000
Alex Jackson, 2014 $4,200,000
Mike Zunino, 2012 $4,000,000
Background: Neidert attracted the Mariners’ attention in an October 2014 outing at the World Wood Bat Championships, when he tossed a two-hit shutout. He missed time during his senior season with elbow tendinitis but returned later in the spring, and the Mariners signed him away from a commitment to South Carolina with a $1.2 million bonus as the 60th overall pick in 2015. Scouting Report: Neidert is a slight righty who draws comparisons with Tim Hudson, and he brings an advanced approach and feel with a fastball/changeup combination. He hits his spots with a 90-92 mph fastball that has reached 94, and he can locate to either side of the plate. His changeup also has potential to be an above-average offering with deception, sink and fade. He’s still developing feel for a slider that he’s learning to throw from his high three-quarters arm slot. Neidert worked on improving his balance in his delivery so that he can more consistently work down in the zone. He needs to be quicker to the plate with runners on base. Observers rave about his competitiveness and advanced approach. Making his lone relief appearance in the Rookie-level Arizona League playoffs, he tossed four shutout innings to help his team advance to the finals. The Future: Neidert has a chance to make his full-season debut at low Class A Clinton in 2016 and has No. 4 starter upside—perhaps higher if his velocity improves.
2015 Club (Class) W L ERA G GS CG SV IP H HR BB SO AVG
AZL Mariners (R) 0 2 1.53 11 11 0 0 35 25 1 9 23 .198

6. Luiz Gohara, lhp Born: July 31, 1996. B-T: R-R. Ht.: 6-3. Wt.: 210. Signed: Brazil, 2012. Signed by: Emilio Carrasquel/Hide Sueyoshi. Background: Gohara returned to short-season Everett for a second straight season in 2015 and showed signs of becoming the power pitcher the Mariners envisioned when they signed him for $800,000 out of Brazil in 2012. The hulking lefty didn’t yield an earned run until his third start—when he gave up five in five innings, an indication of his still less-than-stellar command. Scouting Report: At his best, Gohara overwhelms hitters with a 92-94 mph fastball that tops out in the upper 90s. Lefties hit just .222 against him and struggled to pick the ball up out of his three-quarters arm slot, especially his average, slurvy slider with depth. When things aren’t going his way, Gohara struggles to repeat his delivery and loses command. He’s not particularly athletic and doesn’t always seem to have his limbs moving together. As a result, his 62 strikeouts ranked fifth in the Northwest League, while his 32 walks tied for the most in the circuit. He also ran up a 6.20 ERA. His changeup still is developing and would be more effective at a lower velocity. The Future: Gohara made two spot starts at low Class A Clinton in 2015, yielding just two earned runs over 10 innings, and should get a chance to open 2016 in the Midwest League as a 19-year-old starter.
2015 Club (Class) W L ERA G GS CG SV IP H HR BB SO AVG
Clinton (Lo A) 0 1 1.86 2 2 0 0 10 10 0 6 5 .294
Everett (SS) 3 7 6.20 14 14 0 0 54 67 4 32 62 .305

7. Braden Bishop, of Born: Aug. 22, 1993. B-T: R-R. Ht.: 6-1. Wt.: 190. Drafted: Washington, 2015 (3rd round). Signed by: Jeff Sakamoto.
Best Hitter for Average Drew Jackson
Best Power Hitter Tyler O’Neill
Best Strike-Zone Discipline Drew Jackson
Fastest Baserunner Drew Jackson
Best Athlete Braden Bishop
Best Fastball Edwin Diaz
Best Curveball Cody Mobley
Best Slider Dan Altavilla
Best Changeup Andrew Moore
Best Control Andrew Moore
Best Defensive Catcher Steve Baron
Best Defensive Infielder Rayder Ascanio
Best Infield Arm Drew Jackson
Best Defensive Outfielder Braden Bishop
Best Outfield Arm Alex Jackson
Background: Bishop was a two-sport athlete at St. Francis High in Mountain View, Calif., excelling on the diamond and as a wide receiver. He even received Division I recruiting interest in football. He stuck with baseball, passed on signing with the Braves as a 36th-round pick in 2012 and chose to attend Washington. Scouting Report: Bishop is a natural defender in center field with well above-average speed and a plus arm, but his lack of consistency with the bat caused him to slip to the third round in 2015, where the Mariners happily grabbed the local product. Bishop gets equally high marks for his work ethic and character, notably a charity he started to benefit Alzheimer’s research after his mother was diagnosed with the disease at age 52. A shorter, more direct swing helped him hit .320 at short-season Everett to rank second in the Northwest League. He could stand to be more patient after recording 33 strikeouts and just five walks. Bishop rivals Everett teammate (and 2015 fifth-round pick) Drew Jackson for the fastest runner in the organization, but he lacks Jackson’s polish and aggressiveness as a basestealer. He covers a lot of ground in center field and is an advanced defender well-suited for Seattle’s spacious Safeco Field. The Future: Bishop should team with Jackson again to open 2016 with a Class A affiliate, possibly high Class A Bakersfield.
2015 Club (Class) AVG OBP SLG AB R H 2B 3B HR RBI BB SO SB
Everett (SS) .320 .367 .393 219 34 70 8 1 2 22 5 33 13

8. Andrew Moore, rhp Born: Jan. 2, 1994. B-T: R-R. Ht.: 6-0. Wt.: 185. Drafted: Oregon State, 2015 (2nd round supp). Signed by: Jeff Sakamoto. Video Background: The Mariners believe they got a steal in Moore with the 72nd pick of the 2015 draft, and that the polished former Oregon State ace could move quickly through the system. In similar fashion to fellow 2015 pick Nick Neidert, Moore succeeds with command and control of a four-pitch arsenal more than velocity. Scouting Report: Moore adds and subtracts from an 89-92 mph fastball that touches 94 while locating it to all quadrants of the strike zone. He issued just two walks in his pro debut at short-season Everett, the fewest among any pitcher in the league who tossed at least 20 innings. He keeps hitters off-balance with a changeup that has plus potential. He throws the pitch with deceptive arm speed and gets some sinking action on the offering. Moore mixes in a tight-breaking curveball that has potential to be an average big league offering and a low-80s slider that is mostly used for show. He is a cerebral pitcher who excels at reading batters’ swings and learning their tendencies, though he sometimes overthinks and uses all of his pitches to a fault. The Future: Moore must prove his modest-but-athletic, 6-foot frame can hold up under a pro workload. He could move quickly and profiles as a back-end starter without a dominant pitch.
2015 Club (Class) W L ERA G GS CG SV IP H HR BB SO AVG
Everett (SS) 1 1 2.08 14 8 0 0 39 37 2 2 43 .250

9. Boog Powell, of Born: Jan. 14, 1993. B-T: L-L. Ht.: 5-10. Wt.: 185. Drafted: Orange Coast (Calif.) CC, 2012 (20th round). Signed by: Rick Magnante (Athletics).
Catcher Mike Zunino
First Base D.J. Peterson
Second Base Robinson Cano
Third Base Kyle Seager
Shortstop Ketel Marte
Left Field Tyler O’Neill
Center Field Drew Jackson
Right Field Alex Jackson
Designated Hitter Jesus Montero
No. 1 Starter Felix Hernandez
No. 2 Starter Taijuan Walker
No. 3 Starter Wade Miley
No. 4 Starter James Paxton
No. 5 Starter Nathan Karns
Closer Edwin Diaz
Background: The Athletics drafted Powell but sent him to the Rays in the January 2015 deal that brought Ben Zobrist to Oakland. The Rays later included him in the November 2015 deal that also brought Nathan Karns to Seattle. Powell was suspended for 50 games in 2014 after testing positive for an amphetamine, but he played enough to lead the minors with a .451 on-base percentage. Scouting Report: The Mariners believe Powell’s plus speed and fearless defense will make him a good fit for center field in Seattle. However, his ability to hit on a consistent basis will determine if he plays as a regular or a backup. The 5-foot-10 Powell draws comparisons with fellow diminutive, lefthanded-hitting outfielders Adam Eaton(^) and Brett Gardner for his style of play. He has good bat-to-ball skills and can bunt for hits, and he has drawn 61 walks each of the past two seasons. He’s at his best when working the count and driving the ball to gaps. Powell slumped when he expanded his strike zone and got big with his swing, trying to generate power. He’s an above-average runner but an inefficient basestealer. The Future: Powell will get a shot to make the big league club in 2016, most likely as an extra outfielder.
2015 Club (Class) AVG OBP SLG AB R H 2B 3B HR RBI BB SO SB
Montgomery (AA) .328 .408 .416 238 44 78 6 6 1 22 29 38 11
Durham (AAA) .257 .360 .364 206 22 53 10 3 2 18 32 41 7

10. D.J. Peterson, 1b/3b Born: Dec. 31, 1991. B-T: R-R. Ht.: 6-1. Wt.: 210. Drafted: New Mexico, 2013 (1st round). Signed by: Chris Pelekoudas. Video Background: Peterson’s road to the big leagues hit a significant pothole in 2015, when a 0-for-15 start at Double-A Jackson turned into a season-long slump. The Mariners drafted him with the 12th overall pick in 2013, and his younger brother Dustin, now a Brave, was a second-rounder the same draft. D.J. was hit by a pitch in his pro debut that broke his jaw, but he returned the following season to belt 31 homers between high Class A and Double-A. Scouting Report: Peterson lost weight before the start of 2015 in an attempt to gain flexibility and speed, but it failed to pay off. The Mariners gave him a change of scenery with a promotion to Triple-A Tacoma in late July, but an Achilles injury ended that after just four games. The Mariners would like to see Peterson manage the strike zone better and use the whole field more. Some scouts still believe in his swing, but others don’t think he will hit enough to be a regular. Despite an above-average arm, he is a well below-average defender at third base because of poor range. He spent more time at first base in 2015, likely his permanent home going forward. He’s a well below-average runner but does not clog the bases. The Future: Peterson must show he can hit enough to play first base in a return to Tacoma, but a bigger challenge looms at Seattle’s Safeco Field, which suppresses righthanded power.

Arizona Fall League Top MLB Prospects Hot Sheet (10/28/19)

Ranking the 10 hottest prospects in the Arizona Fall League last week, beginning with the D-backs' Seth Beer.

2015 Club (Class) AVG OBP SLG AB R H 2B 3B HR RBI BB SO SB
Jackson (AA) .223 .290 .346 358 39 80 19 2 7 44 31 90 5
Tacoma (AAA) .214 .214 .286 14 0 3 1 0 0 0 0 3 0

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