Kristi Simmons

SeattleClubhouse Top-50: Seattle Mariners' prospects No. 5 through 1

The final installment of our 2016 Top-50 prospects in the Seattle Mariners’ organization. Each player review is complete with scouting notes and quotes from various baseball sources from inside and outside of the M’s organization. Our initial list of close to 100 names was trimmed to the final 50 with that help, but the final rankings are the opinion of SeattleClubhouse and don’t necessary reflect the views which we take into consideration while making the final cut down.

Here at SeattleClubhouse, our primary goal in covering the Seattle Mariners is to give our readers exclusive, in-depth information on players in the organization from the foreign Rookie League teams all the way to the Major Leagues. We do this by looking beyond just statistics and typical web resources and using direct input from the Mariners' staff -- including Jeff Kingston, Andy McKay, Tim Allison, Tom McNamara, Tim Kissner and others -- and other respected baseball contacts from outside of the organization to help develop our unique set of rankings. SeattleClubhouse's personal taste and scoring plays into the determination of where the prospects land on the list, too; that scoring system is a combination of potential ceiling, perceived likelihood of reaching that ceiling, the most probable outcome for the player and their proximity to cracking the 25-man roster, but also age, level, tools, etc. are weighted. The aim is to give the readers rundowns on the names in the Seattle system that are worth tracking for the coming season and maybe even pinning future MLB hopes on. 

We do updates on a smaller scale throughout the year, but just as with every pre-season list, this pre-2016 countdown is 50 deep. The landscape of the organization has definitely changed since our last report, even in the Top-5, so this extended breakdown will be much different as it is a true fresh look at the organization as it now exists, with completely up to date late- or post-season input. The reports will be thorough for all players covered, but they'll get more so as we climb towards the top of the heap. And while four of the ten pieces will be free for anyone who visits the site, the other six will be subscriber only.

As you will see during this countdown, many of the higher-ceiling prospects in the Mariners’ system are on the younger side, residing in the lower levels of the minor leagues. So while the system isn’t as bereft of talent as the common narrative seems to be, there aren’t many MLB-ready prospects knocking on the door, and that is primarily what leads to this generally being considered a bottom-third system in baseball.

Each player we cover this year will be presented with a photo (when available) and bio info as well as the level at which they ended during the 2015 regular season. Players who have finished their age-26 season and those who have exhausted their Rookie status per Major League guidelines are not eligible for consideration. Discussion in the forums is welcome, but until the entire Top-50 is released for all (after the individual pieces are finished), please keep discussion on the information from subscriber pieces in the subscriber forums.

Previous Reports:

Nos. 50 through 46

Nos. 45 through 41

Nos. 40 through 36

Nos. 35 through 31

Nos. 30 through 26 (SUBSCRIBER ONLY)

Nos. 25 through 21 (SUBSCRIBER ONLY)

Nos. 20 through 16 (SUBSCRIBER ONLY)

Nos. 15 through 11 (SUBSCRIBER ONLY)

Nos. 10 through 6 (SUBSCRIBER ONLY)

And now we've finally reached our final report; the top five prospects in our sixth annual Top-50 countdown, representing the very best in the Seattle Mariners' organization. Enjoy!

Seattle Mariners

5. Luiz Gohara – LHP, 6’3”, 210, SS, 7/31/96, L/L

4.15 6 21.2 22 9 27 1.431 9.1 0.4 3.7 11.2 3.00
6.70 13 49.2 57 26 53 1.671 10.3 1.1 4.7 9.6 2.04
5.54 16 63.1 77 38 67 1.816 10.9 0.6 5.4 9.5 1.76
5.75 35 134.2 156 73 147 1.700 10.4 0.7 4.9 9.8 2.01

Gohara, who was number 17 on our countdown last year, has carried a very high profile as a prospect since becoming a rare signing out of Brazil as a 16 year old. But having now wrapped up his third pro season, the rotund left-hander still hasn't mastered Short Season ball and the frustrations with his conditioning, work ethic and consistency are still more prevalant than his dominance on the mound. After failing to record more than three outs in three of his 13 starts in 2014 for Everett, Gohara opened 2015 pitching as an 18 year old for Clinton in the Midwest League, twirling five shutout innings at the end of May when they were short on pitching. Returned to Everett for the Northwest League season that started in June, Luiz threw two great games for the AquaSox, striking out a total of 17 and not allowing an earned run in two separate six-inning starts. But it all went downhill from there, as the left-hander -- who likely pitched 2015 closer to 250 pounds than his listed weight of 210 -- put up a 7.58 ERA and a 2.18 WHIP the rest of the way, making it through just 46 1/3 innings in his final 13 starts of the year, lasting past the 5th inning only once.

The electric stuff is there at times -- particularly with the fastball -- but the consistency, effort and conditioning are frustrating. "Conditioning has always been an issue with him, and this season he seemed even more overweight," said one disappointed member of the organization. That staff member continued his assessment of Gohara with this take: "The velocity is inconsistent and the 'control' is shaky at best. And the secondary offerings…meh. He doesn’t seem to be innately competitive and he has a tendency to pout when things don’t go his way." And yet, the left-hander has struck out 147 in 134 2/3 minor league innings and ran a ground ball rate of 54.7% in 2015 and 60.2% to date.

Despite the stuff that he has in him and despite repeating the NWL in 2015, right-handed hitters torched Gohara to the tune of a .325/.434/.474 slash at a level where the league OPS was just .685. That shouldn't happen to an elite level really shouldn't even happen to a fringe MLB prospect, but it happened to Gohara. Two years in a row now. Even though he's still quite young, the lefty truly does run the risk of a precipitous drop in the rankings if 2016 isn't a good showing for him. The 'mini-C.C. Sabathia' as he was dubbed to me by one coach fresh after signing isn't 'mini' in any way any more, and the pressure on him to perform in 2016 won't be small, either.

Gohara's fastball still has mid- to upper-90s ability, and he gets good run on the pitch, but he hasn't controlled it well since pitching for Pulaski in 2013, and he really hasn't ever shown enough command of the offering to have it be an elite pitch despite the elite velocity from the left side. His breaking balls (or maybe two speeds that he throws his slider at) are both inconsistent and tend to flatten out as Luiz loses his release point, and his changeup -- which showed promise early -- isn't fooling anyone these days. As little as he's shown, Gohara does figure to see Clinton full-time in 2016, if for no other reason than to have a full compliment of minor league games to get enough starts in to find some consistency and take some steps forward. The ability is still in there for Luiz, but at this point it isn't clear if he has the mental fortitude and self-drive to reach his lofty potential.

TOP TRAIT(S): Arm speed, frame

Seattle Mariners

4. Tyler O'Neill – OF, 5’11”, 210, A+, 6/22/95, R/R

116 31 5 3 1 15 12 27 .310 .405 .450 .855
258 58 11 0 13 40 21 85 .251 .326 .468 .793
449 106 21 2 32 87 29 137 .260 .316 .558 .874
823 195 37 5 46 142 62 249 .264 .332 .515 .847

O'Neill, 13th on last season's countdown after debuting at 25th the year before, was one of few M's prospects who outperformed expectations in 2015. Seattle's 3rd round pick in the 2013 Draft took a major step forward in 2015 while seeing his most extensive action, tying for second in the minor leagues (and tops in the organization with Jabari Blash) with 32 home runs, hitting one in just over every 14 plate appearances in a season that saw him take a break to represent his country in the Pan Am Games. And in those games for Canada -- which held him out of Bakersfield's lineup for 20 days -- Tyler excelled as one of the youngest participants in the field, hitting in the middle of the order and crushing three homers. He would hit three more for Peoria in the AFL as the second youngest player there, and while the plate discipline numbers still aren't great, it's easy to see the progress that the right-handed slugger is making. As Chris Gwynn told the Seattle Times in August, "He’s figuring it out. He’s not a finished product, but he’s going in the right direction."

For those who saw O'Neill every day, the praise flows easily. The Blaze's Dan Besbris' full take on what he saw in 2015 from O'Neill goes like this: "I'm not sure what I can add that hasn't already been written. Tyler hit some baseballs so far last year that I actually burst out laughing on air. No home run call. Just laughter. We're talking moonshots; towering flyballs that carry, and carry, and then suddenly disappear some 420-plus feet away. 20-year olds just don't hit baseballs like that. The last one I can remember seeing with that kind of sock in the Cal League was Justin Upton or Chris Davis. O'Neill is quick, his bat speed is ridiculous, and when he's on, he's a juggernaut. And through all of that, O'Neill's opposite field homer off the videboard in Inland Empire is still the one that sticks in my memory, because he waited on a fastball, and smashed it over the fence in deepest rightcenter, clearing the wall by probably 30-40 feet .... the other way!"

Above is one of those laughable shots that Besbris talked about. Just huge power. And while that one was launched out to left center field, O'Neill showed this past season that he was aware that his power would play all around the park. Having pulled all but one of his home runs in the minors coming into 2015, Tyler hit 14 of his 32 dingers this season up the middle or the other way. 

Tyler grew up a Mariners fan, and he told SeattleClubhouse back in 2013 that he wants to be one of those players that kids want to emulate and learn to love the game from. Despite being just 20, that dream doesn't seem too far away for O'Neill now. As evidenced by his numbers, his plus-plus power is showing more in games, and while O'Neill's attacking style still yielded a 30.5% strikeout rate, he is advancing as a hitter and showed some patient stretches that enabled him to really torch the ball. Despite being the muscular son of a bodybuilder, O'Neill has a slim waist and is quicker and faster than you'd expect someone with his power to be, and he's 23-for-32 in steals in the minors overall, 16-for-21 for Bakersfield this past year. As a former catcher, he has a strong arm, although he is still adjusting to throwing from the outfield. He's played some center field and could actually currently handle that assignment in terms of range, but he remains a little raw in his routes. O'Neill is an all-out effort guy, and he shows strong instincts, too. The jump to Double-A is a tough one, but having overcome some earlier bouts with anger, O'Neill appears to be ready for the challenge in 2016.

TOP TRAIT(S): Strength, power, speed, athleticism

Seattle Mariners

3. D.J. Peterson – 1B, 6’1”, 210, AAA, 12/31/91, R/R

230 63 11 1 13 47 20 42 .303 .365 .553 .918
547 147 31 1 31 111 45 116 .297 .360 .552 .912
407 83 20 2 7 44 31 93 .223 .287 .344 .632
1184 293 62 4 51 202 96 251 .273 .336 .480 .816

Peterson's struggles in 2015 were a mirror image of the overall struggles of the Mariners' system. Our number two prospect in the system following his debut in 2013 and the top ranked prospect a year ago following his 31 homer, 111 RBI year, D.J. saw his OPS dip nearly .300 points and his home run total fall to seven in a lost year playing for Double-A Jackson. Seattle apparently tried to kickstart the right-handed hitter's bat in August with a promotion to Triple-A Tacoma, but he was quickly injured after a non-descript four games and his disappointing season was in the books. Sent to the AZL for the second straight season to try and end 2015 with something other than a terrible taste in his mouth, Peterson hit just .209/.321/.388 there and ended the year on a 7-for-49 skid. Even though it was his 2013 season that was ended when his face was broken by an errant fastball -- the first time that Peterson had been hit by any pitch as a pro -- it seemed like this past year was really when that injury messed with Peterson's mind. His approach seemed very pull conscious, and the predictible steady diet of soft stuff away did him in.

"It's not a secret that 2015 wasn't the year Peterson envisioned," Jackson's Brandon Liebhaber told me, "but he showed some encouraging signs late. The genesis of a lot of his problems was his approach at the plate. He was very pull-happy and got fed a steady diet of offspeed pitches low and away. But he was constantly working with coaches to get it right and remain more balanced at the plate." It was definitely hard to watch, but "the tools are still there," Liebhaber says. D.J. didn't homer until game 19 on the season, had a .708 OPS in his 'best' month and went just 5-for-46 (.109) against left-handed pitchers, all while transitioning to being primarily a first baseman on the defensive side of the ball, which obviously lowers his future potential value. Whatever the tools, that doesn't cut it for a prospect.

But Peterson does have some big time power in him. "I am not comparing the two players to be clear," said Liebhaber, "but Peterson and Miguel Sano were the only two hitters I saw that hit true opposite-field home runs this season. That isn't easy to do at any Southern League ballpark, and that is especially true in Jackson where the walls are 16 feet high." Doing that -- staying back on the ball and going the other way for power -- has to be a major focus for Peterson in 2016. He made some swing changes with a non-affiliated hitting coach before 2015 that I hear the organization wasn't too happy about, and undoing some of that was tied into his plan late in the year and into this offseason. Assuming the swing is where he and the M's want it, being able to chase away any of those lingering demons of the fastball that broke his jaw and had his mouth wired shut for six weeks is what will enable D.J. to find success. Even though he had a big year after that horrific injury, I spoke with some PD staff and a couple of scouts who felt that thought lingered with him in 2015.

Viewed as the top college bat in that 2013 Draft when the M's took him 12th overall, Peterson's approach has definitely regressed. His hit tool is presently below average, but if he can get back to the approach and selectivity that he showed in college and with Everett, D.J.'s plus power will have a better opportunity to play. Now relegated to first base, his strong arm doesn't come into play much, and he still doesn't have ideal lateral quickness, although he should be able to be an average (right-handed) defensive first baseman. He isn't much of a runner, either, which means that all of Peterson's future value is tied to his currently questionable stick. A rebound in 2016 will likely first have to come back in Double-A, where the 24 year old figures to open. 

TOP TRAIT(S): Power, approach

Seattle Mariners

2. Edwin Diaz – RHP, 6’3”, 165, AA, 3/22/94, R/R

5.21 9 19.0 12 17 20 1.526 5.7 0.9 8.1 9.5 1.18
1.43 13 69.0 45 18 79 0.913 5.9 0.7 2.3 10.3 4.39
3.34 24 116.0 96 42 111 1.190 7.4 0.4 3.3 8.6 2.64
3.82 27 141.1 123 46 145 1.196 7.8 0.5 2.9 9.2 3.15
3.26 73 345.1 276 123 355 1.155 7.2 0.5 3.2 9.3 2.89

Diaz is another one of the few prospects in Seattle's system who had a good year in 2015, and the slight right-hander impressed quite a bit as he climbed to Double-A in his 21 year old season. Climbing from a relatively unknown commodity out of Puerto Rico and ranking 45th before 201312th prior to 2014 then landing at No. 7 a year ago, Diaz's repertoire has changed a bit as he's grown in the system. Working primarily fastball-slider now, Diaz mowed down the Cal League in his first seven starts of the year, striking out 42 and allowing just 30 base runners through 37 innings of 1.70 ERA pitching. The road definitely got tougher when he climbed the ladder, but Diaz turned in 10 starts of five or more innings allowing three runs or less for Jackson and struck out more than 26 percent of the Southern League hitters he faced. His slider lost effectiveness late in the year and it's possible that his 141 1/3 innings were wearing on him. That's not to say that he can't project as a starter long-term. In fact, the organization is confident that despite his slight build, Diaz can handle a full starter's workload as he matures. Perhaps the most encouraging part of Diaz's 2015 was that his walks-per-nine went down and strikeouts-per-nine went up even while moving up two levels, which means not only better hitters, but a more consistent, usually tighter strikezone.

That is a testament to the fact that the stuff plays, and the arm speed and arm action Diaz has is electric. He can be downright dominant for long stretches at times; he showed that for Jackson when he tied the club record and came within one of tying the Southern League record in a June start by striking out seven straight batters. Not many starting pitchers can match his velocity, and when Diaz is commanding that electric fastball and has the right release on his slider, the combination is deadly. One scout who saw Diaz in California offered this quick report on him: "His arm is fantastic. Great whip, huge velocity. He isn't always consistent, but the arm is very, very good. The ability is there."

Jackson's Brandon Liebhaber had an up close look at the 20 starts Edwin made in Double-A, and he had this to say about the righty: "It's easy to see why Diaz is so well-liked. His ceiling is extremely high after spending most of 2015 as the youngest player on Jackson's roster. Though his motion isn't the most fluid, he makes hitting the high 90s on radar guns look easy. He was frequently kept on a short leash this season, but often looked as though he could continue with ease. Until late in the year, he was the only Jackson starter to make it through seven innings and he did that three times. Diaz was able to have success while using his fastball almost exclusively at times, though he did work on using his slider and changeup with more frequency. At times, his biggest enemy can be himself. He is very emotional, and that's something he is working on keeping in check. It has its benefits, too, as he was certainly fired up when he hit 98 at the Futures Game. Was told by some that Diaz was seen in 2012 as having better upside than fellow Puerto Rico native and current Twins' prospect Jose Berrios. If he puts it all together, Diaz could be special. At worst, I see him as an impact reliever on the strength of his fastball-slider combination alone."

As you can see in that one pitch video, Diaz has some funk in his delivery, with long limbs and a little bit of an odd kick in his front leg before release. He also throws across his body a bit, stepping more towards the right-handed batter's box than directly to his catcher. It's the type of delivery that we see from junkballer lefties at times. But Diaz touches the upper-90s regularly with his fastball, working comfortably at 93 to 95. The slider tends to flatten out when Diaz lets his release point drop, but even then it has enough movement to it that he can get swinging strikes on the pitch, but it is a better offering for him when he is firm and tigher with it, usually pushing it in around 85. His change is a decent offering when he commands it, and it has good mph separation from his fastball, but it is clearly a third pitch. That being said, Diaz's movement on his two-seamer helped him limit left-handed bats to just a .205 mark and a 27.1% K rate, compared to a .268 clip and 22.5% strikeout rate versus right-handers. He may see some more starts in Jackson to open 2016, but Seattle figures to challenge Edwin with Tacoma in the coming year, and with just a few minor steps forward he could be big league ready by season's end.

TOP TRAIT(S): Arm speed, fastball, athleticism, slider

Seattle Mariners

1. Alex Jackson – OF, 6’2”, 215, SS, 12/25/95, R/R

94 23 6 2 2 16 9 24 .280 .344 .476 .820
318 56 17 1 8 38 27 96 .207 .318 .365 .683
412 79 23 3 10 54 36 120 .224 .324 .391 .715

A consensus pick as one of the top bats in the 2014 Draft, Jackson was aggressively assigned to Clinton to open 2015 and struggled terribly there, striking out in 17 of his final 50 trips while picking up just seven hits in that stretch. He'd leave Clinton with just a .157/.240/.213 slash. There is talk that that stat line was possibly at least partly due to his shoulder injury, but nevertheless, heading back to Arizona for a month before eventually ending up in Everett was a very good thing for him. No. 2 on our pre-2015 Top-50, the converted catcher took well to the outfield defensively and showed natural ability out there, and his bat started to show some promise with the AquaSox, too, as there were times that Jackson would spray rockets from gap-to-gap. He was OPSing over .900 heading into the last week of the season before ending a little soft. Even with the positive signs, Alex still posted a strikeout rate of nearly 31 percent, didn't hit for a strong average and ended up with a solid but unspectacular .239/.365/.466 slash in the NWL. Regardless, Baseball America named Alex the No. 4 prospect in the Northwest League following the season.

Jackson has been the lone M's prospect getting love from other outlets, and ranked 96th in our league-wide Top-100 here at Scout. But even though the natural talent is quite obvious, he isn't a polished, surefire player. "He seems to be getting by with natural ability at the plate," said one long standing member of the organization. "The swing and power are legit, but he needs to improve significantly in his ability to recognize pitches. Defensively he’s slightly above average; he takes good routes and has a strong arm suited for RF. He needs to take a step forward this season." There were whispers that maybe Jackson's status as a highly regarded prospect and his history of being 'the man' rubbed off on his attitude a bit, but no one mentioned that when I spoke with the PD Staff about Jackson in January. "He worked really hard in Everett and worked his tail off down here [in Arizona], too," Jack Howell told me. He was first or second on every prosopect ranking list that I got from members of the Seattle front office and his size, strength and swing look like they are special.

As evidenced by the spray chart above, the power Alex has at this young age plays all around the park. Only nine of his 26 extra base hits in 2015 were pull-side, and he does a good job of letting the ball travel and not trying to sell out for power, which is impressive for a high school bat. If you squint, you can see a little Miguel Cabrera in his swing. Jackson obviously has miles and miles go to be mentioned in the same breath as a hitter of that quality, but the tools that he shows in the box are apparent and make it easy to see why Seattle popped him at 6th overall in the 2014 Draft.

Jackson was a catcher in high school, but he wasn't totally foreign to the outfield, as his coach at Rancho Bernardo told me right after the Draft that Alex frequently worked out with the outfielders in drills. His comfort out there was evident in Everett, as he got good jumps, made smart throws and picked up eight outfield assists from right field for the AquaSox, but he does look a bit slower than I'd expected as he gained some weight (good weight) this season. The bat is clearly the top tool here, though. Led by plus bat speed and plus power and showing a good bat path and willingness to go the other way, you can see that Jackson could easily be a plus hitter for average with 25-plus homer potential. But if the pitch recognition or selectivity and perceived attitude issues don't improve, it is also possible that Jackson stays on a flat development path as more of an all-or-nothing bat. 2016 will be a big year for Alex, and the Midwest League will likely be the setting for the challenge.

TOP TRAIT(S): Bat speed, power, arm

That does it for this report and puts a wrap on our 10 week in-depth reports that make up our Annual Top-50 Prospect countdown of the best in the Seattle Mariners' organization. Be sure to check back soon for a take on some of the names that just missed this list, and stay tuned for all of our reports throughout spring training and the entire year ahead of action in Seattle's system.

Looking for more Mariners news, articles and player interviews? Want to keep up with which prospects are hot and cold for the M's? "Like" SeattleClubhouse on Facebook and follow SeattleClubhouse site Editor Rick Randall on Twitter at @randallball.

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