Mariners top 20 prospects 2023: Keith Law ranks Seattle’s minor league farm system

The Mariners had a top-five system not that long ago, but promotions — including last year’s AL Rookie of the Year — and a couple of big trades wiped out the top tier of talent. The talent here that’s close to the big leagues is mostly lower-ceiling guys who project as reserves, while they have a very promising group of higher-ceiling guys who’ll spend this year at High A and below.



MLB prospect rankings 2023: Keith Law’s complete guide to every farm system

The ranking

1. Harry Ford, C (Top 100 ranking: No. 65)

Age (as of July 1): 20 | 5-10 | 200 pounds
Bats: Right | Throws: Right
Drafted: No. 12 in 2021

Ford was the Mariners’ first-round pick in 2021, the first time they went for a high school player with their first pick in eight years (only to have them do it again in 2022 with Cole Young). He’s a very athletic catcher who is probably not going to stay behind the plate, but has shown enough in the box to project as an above-average regular at some other position. His full-season debut saw him post the 11th-best OBP of any player in full-season ball (min. 300 plate appearances), with a line of .274/.425/.438 and a 23 percent strikeout rate. He makes good decisions at the plate, which has allowed him to get away with an unorthodox swing that’s very rotational and aimed at impacting the ball as hard as he can. He has way more work to do behind the plate, where he’s below-average at framing and receiving and only slightly better at throwing, even with some arm strength. He’s a plus runner, though, and could probably move to center field, which would also free him up to get more at-bats over a full season. For now, the Mariners seem committed to him staying at catcher, which may slow down his development a little bit. His approach and 20/20 potential would give him a chance to be an above-average or better regular if he can find a position up the middle where he can stick.

2. Bryce Miller, RHP (No. 75)

Age: 24 | 6-2 | 180 pounds
Bats: Right | Throws: Right
Drafted: No. 113 in 2021

Miller was an erratic mostly-starter at Texas A&M who showed power stuff but a long arm swing and 35 command and control, walking 14 percent of batters he faced in his draft year, but the Mariners took a bet on his athleticism that is already paying off. He’s now a three-pitch starter who has close to average control and continued to improve even as the season progressed, including promotions to High A and then Double A over the summer. Miller sits 94-97 mph now and has bumped 100, with a high spin rate on the pitch that allows him to pitch primarily with his fastball. He pairs it with a plus slider that gets right-handed hitters to whiff and serves as a usable chase pitch for lefties. His changeup is clearly his third pitch right now, although it’s serviceable and already better than it was in college, which I realize makes it sound like his changeup was actually a student but maybe failed organic chemistry. It’s a matter of consistency, as the pitch is effective when he stays on top of it and lands it below the middle of the zone, but he leaves it up too often and loses the deception that makes it work. His arm action is still on the long side but it’s more fluid and he’s repeating it better. He’s so athletic and already has become so much more of a complete pitcher, rather than a thrower, that I’m willing to bet on further upside. He could be a No. 2 starter, and while there’s reliever risk, he’d be a high-end weapon out of the bullpen if that comes to pass.

Bryce Miller (Michael Miller / The Eagle)

3. Gabriel Gonzalez, OF

Age: 19 | 5-10 | 165 pounds
Bats: Right | Throws: Right
International signing in 2021

Gonzalez signed in February 2021 for a $1.3 million bonus, and the Venezuelan outfielder now boasts a .307/.393/.491 line in 511 plate appearances in pro ball between the DSL, ACL, and Low A, all before his 19th birthday. He’s a mature-bodied right fielder with a 70 arm and plus power now that might end up at 70 as well, showing an advanced approach at the plate for his age already, although his OBP is inflated by his habit of getting hit by pitches because he stands right on top of the plate (17 times in 290 plate appearances in 2022 … really, stop that, before you break something). He doesn’t chase, and he swings at strikes, with the chance if everything works out for a 6 bat with 7 power. He’ll probably be a fringy defender outside of the arm, and there is big risk in such a bat-driven profile, but that’s star upside. He’s another guy from the “just missed the just missed” list.

4. Cole Young, SS

Age: 19 | 6-0 | 180 pounds
Bats: Left| Throws: Right
Drafted: No. 21 in 2022

The Mariners’ first-round pick from 2022 had an incredible pro debut after signing, hitting .367/.423/.517 in just 17 games between the ACL and Low A, never looking overmatched against probably the best pitching he’d seen in his life. He’s got a lot of 55ish tools, now or projected, with a chance to stay at shortstop, above-average speed, obvious feel to hit, maybe getting to average power at his peak. He worked to clean up his swing last offseason, which is probably what propelled him into the first round last year. The feel for contact is impressive, and if he stays at short, the Mariners will have a future All-Star.

5. Bryan Woo, RHP

Age: 23 | 6-2 | 205 pounds
Bats: Right | Throws: Right
Drafted: No. 174 in 2021

Woo has plus velocity and an above-average to plus changeup, but the best thing I can tell you about him is this: In his second rehab start back from Tommy John surgery, he took a 108 mph line drive to his face off the bat of James Wood, who is 6-7, 240 pounds. Woo hit the ground for quite some time. He came back six days later for his next scheduled outing and hit 98 mph. The fastball has good ride to it, and he has an incredible delivery that scouts rave about like they’re talking about something by one of the Dutch Masters. The command isn’t great, and it wasn’t great before the elbow injury, but he projects to a back-end starter role with wide variance. Depending on command and the development of his breaking ball, he could end up a No. 3 or better.

6. Michael Arroyo, SS

Age: 19 | 5-10 | 160 pounds
Bats: Right | Throws: Right
International signing in 2022

A Colombian infielder signed last January for $1.3 million, Arroyo was one of the best hitters in the DSL with a .314/.457/.484 line and nearly as many walks as strikeouts. He’s got a strong right-handed swing that should produce above-average power as he fills out, with solid contact quality already as a 17-year-old last season. He’s probably going to move to third or second, lacking the range for short and with just an average arm that makes second a little more likely. He had a minor wrist injury and didn’t participate in instructs.

7. Emerson Hancock, RHP

Age: 24 | 6-4 | 213 pounds
Bats: Right | Throws: Right
Drafted: No. 6 in 2020

Hancock missed time last year with a lat injury, and struggled with the longball when he did pitch, giving up 16 homers in 98 Double-A innings, almost all on fastballs. His command has never been a strength, and when he leaves the four-seamer, which sits 93-94 mph and bumps 96, in the upper half of the zone, hitters can square it up. The good news is that overall he didn’t give up a ton of hard contact, and the slider was at least a 55, and arguably the changeup was too. It’s a three-pitch mix and he’s just on the low side of average control, enough to call him a fourth or fifth starter who arrives later in 2023, but with a little more upside if he improves the fastball command even a little bit.

8. Walter Ford, RHP

Age: 18 | 6-3 | 198 pounds
Bats: Right | Throws: Right
Drafted: No. 74 in 2022

The Vanilla Missile was the Mariners’ third pick last year, taken with their competitive balance selection after the second round, as the team rolled the dice on big upside after taking a safe college player with the previous pick. Ford was one of the youngest players in the class, and he has hit 97 mph, sitting 94-95 with a delivery that drives the ball down in the zone. His lone secondary pitch is a hard downward-breaking slider, but he needs to develop a changeup at the very least and might need something else to help him pitch more east-west, with everything oriented north-south now. He’s very young, just turning 18 in December, and is athletic and projectable, but he might take more time to develop than his peers from this draft class.

9. Jonatan Clase, OF

Age: 21 | 5-8 | 150 pounds
Bats: Switch | Throws: Right
International signing in 2018

Clase was my sleeper pick for the Mariners last year, but I would say he broke out about halfway, with a very respectable .267/.374/.463 line as a 20-year-old in Low A — especially one who’d missed almost all of 2021 — but a 26.6 percent strikeout rate and a bit of a drop in his speed from the year before. He’s more of a 60/65 runner now rather than close to 80, still a plus defender in center, and he’s a switch-hitter who’s better from the left side but capable enough right-handed to keep doing it. The contact rate is the one concern here, because the tools are real and he has a fourth outfielder floor if he doesn’t see his whiff rates rise as he moves up the ladder. I’m cutting him a little slack because he had just 57 plate appearances between 2019 and last year due to the pandemic and injury.

10. Zach DeLoach, OF

Age: 24 | 6-1 | 205 pounds
Bats: Left| Throws: Right
Drafted: No. 43 in 2020

DeLoach should be at least a solid platoon guy in an outfield corner, with a .388 OBP last year against right-handed pitching, but his power right now is light for every day duty. He has excellent pitch recognition and it translates not just into walks but good swing decisions, so if he could add some strength he’d be well set up to get to 20+ homers a year after hitting 14 in each of the last two full seasons. The contact quality is just fair, though, and he’s not a plus runner or plus defender in either corner, which has him more in the extra outfielder/platoon guy bucket. I don’t think he’s a launch-angle modification guy, but anything that gets him to more high-quality contact would help.

11. Taylor Dollard, RHP

Age: 24 | 6-3 | 195 pounds
Bats: Right | Throws: Right
Drafted: No. 137 in 2020

I do not care about pitcher won-lost records — in fact, I almost never even notice them — but Dollard went 16-2 last year in Double A, and despite the fact that it is utterly meaningless for projecting his future, something about that triggered a vestigial memory in me from the 1980s when I thought pitcher wins were important and thought anyone with a won-lost ratio that big had to be good. Anyway, Dollard’s a fine prospect but not, uh, an 8:1 won-lost guy. He pitches backward, using his slider more than his 90-92 mph fastball, with the slider a solid-average pitch that plays up because he locates it so well. He throws both pitches for strikes and even dominated lefties last year while leading with the slider, as he has a changeup for left-handed batters but still works mostly slider/fastball to them. I don’t see more than a fifth starter here but could see him pitching for a while in that role.

12. Axel Sanchez, SS

Age: 20 | 6-0 | 170 pounds
Bats: Right | Throws: Right
International signing in 2019

Sanchez is a plus defender at short with a plus arm and great instincts in the field, maybe the best shortstop in the system other than the just-signed Felnin Celesten. He’s a fringy runner but the hands and reads off the bat will keep him at short in the long term. At the plate, he’s a high-contact hitter with just 40 power; he went off in the Cal League, with 8 homers in 33 games, but the Cal League itself is homer-friendly and half of Sanchez’s homers came at Stockton, whose pitching staff gave up 204 homers in 132 games — 50 percent more homers than the next-highest team in the league. He just turned 20 in December so he has time to gain strength. He has to add some to profile as a regular in the big leagues.

13. Tyler Locklear, 3B/1B

Age: 22 | 6-3 | 210 pounds
Bats: Right | Throws: Right
Drafted: No. 58 in 2022

Locklear was the Mariners’ second-round pick in 2022, a performance draft after he did everything you’d want in the spring for VCU, but did so against weaker competition in the Atlantic 10 after a bad summer in 2021 on the Cape. His swing is very compact and direct, but he’s strong enough for plus power even with the short path. He hasn’t seen much good velocity and I’m not sold on the bat speed being enough for that. He’s played third but is more likely to end up at first, so there’s big pressure on the bat. I was skeptical of the pick, but there were other teams in on Locklear in the same range of the draft, so the Mariners weren’t on an island here, and if he hits better velocity in High A this year they’ll have a potential regular.

14. Lazaro Montes, OF

Age: 18 | 6-3 | 210 pounds
Bats: Left | Throws: Right
International signing in 2022

Montes signed in January 2022 for a $2.5 million bonus, and the Cuban outfielder went to the DSL as a 17-year-old and was a big three true outcomes guy, with more than half his plate appearances ending in a strikeout (33 percent), a walk (16 percent), or a homer (4.5 percent — 10 homers in 55 games). It’s plus-plus power, maybe getting to 80; you might say he hits Laz rockets when he squares it up. He’s limited to the outfield corners, though, so he’s got to make more contact to end up a regular. It’s a selection issue rather than anything wrong with the swing, which gives me a little more hope he can figure it out.

15. Ashton Izzi, RHP

Age: 19 | 6-3| 165 pounds
Bats: Right | Throws: Right
Drafted: No. 126 in 2022

Izzi was the Mariners’ fourth-round pick in 2022, a super-projectable high school right-hander with some promising elements to an inconsistent delivery that might improve as he just adds some muscle. He’s 6-3, 165 pounds, so there’s a ton of room for growth — I don’t know how he looks now but wouldn’t be surprised if he came back bigger this spring — and he gets on top of the ball well for depth on the curveball. He’s further away than Walter Ford, but there’s a lot to like here in the athleticism and projectable build.

16. Isaiah Campbell, RHP

Age: 25 | 6-4 | 230 pounds
Bats: Right | Throws: Right
Drafted: No. 76 in 2019

Campbell’s a straight reliever now and his stuff ticked up with the move to the pen, sitting 95-97 mph with a plus slider that gets right-handed hitters to flail at it out of the zone. He throws both pitches for strikes and didn’t have any issues with left-handed batters between High A and Double A last year. Right now, he looks like a guy who’d roll out of any bullpen in the seventh or eighth inning.

17. Kaden Polcovich, 2B

Age: 24 | 5-10 | 185 pounds
Bats: Switch | Throws: Right
Drafted: No. 78 in 2020

It took Polcovich almost a full year at Double A to adjust to the better pitching there, but he was good enough in the second half of 2022, hitting .263/.361/.478 with a 20 percent strikeout rate, to regain some prospect status. He’s a 55 runner with 55 power and has a good eye at the plate, although he has trouble with the … slider, actually, it’s the slider that gives him fits much more than the curve. He’s played some third and short and should make his way to the majors as a utility infielder. If he can lay off the slider down and away — easier said than done — he actually could still be a regular at second.

18. Tyler Gough, RHP

Age: 19 | 6-2 | 205 pounds
Bats: Switch| Throws: Right
Drafted: No. 276 in 2022

Gough sits in the low 90s with good spin on a curveball that projects to a 55, with a rough delivery that starts with a super-short arm action and finishes with a head-whack. The Mariners signed him for $275,000 in the ninth round, a little more than double the slot value for the pick, to get him to skip his scholarship to Oregon, which might be the right call for him given the help he needs right now to clean up the delivery. He has a third pitch in the changeup and has more present strength with less projection than guys like Walter Ford or Izzi, perhaps someone who’ll move a little faster in the low minors but offers a lower ceiling. Without any mechanical changes, though, he’s more likely a reliever.

19. Prelander Berroa, RHP

Age: 23 | 5-11 | 170 pounds
Bats: Right | Throws: Right
International signing in 2016

Acquired in a midseason trade from the Giants for Landon Snyder, who is definitely a real player and not someone I just made up, Berroa is up to 99 mph, sitting 95-97, with what might be a 70 slider. He doesn’t throw the fastball for enough strikes, with fewer than half of his fastballs ending up in the zone, and he walked 15 percent of batters he faced last year. The delivery is fine, or at least not an impediment to him walking fewer guys. He’s worked as a starter so far and I might leave him there to try to improve his control, although obviously with two plus pitches and huge walk rates he’s probably a reliever in the end — maybe an elite one. Also, I did make up the player he was traded for — the Giants actually traded Berroa for Donovan Walton.

20. Juan Then, RHP

Age: 23 | 6-1 | 200 pounds
Bats: Right | Throws: Right
International signing in 2016

Then pitched for the DSL Mariners in 2017 as a 17-year-old, then Seattle traded him to the Yankees before 2018 and reacquired him after that, so it feels like he’s been on these lists for a decade or so. He missed the first four months of 2022 with elbow problems but returned to the AFL with the same stuff he’s generally had, working mid-90s with a cutter and a two-seamer (which might be his attempt at a changeup, given its action) at 90-91. Even before the elbow issues he was probably going to the bullpen, as he has close to average control but maybe 40 command, and the third pitch probably won’t be good enough for him to face lefties two to three times in a game. He might be out of options after 2023, although he could qualify for a fourth, but there’s some urgency here to get him to the big-league roster.

Others of note

The Mariners went well over slot in the third round to sign Michael Morales, a high school pitcher in Pennsylvania, in 2021 based on his clean delivery and chance for plus command, although his stuff had tapered off at the end of his senior year. The stuff didn’t bounce back in 2022 and he struggled with giving up hard contact in Low A while also throwing only 62 percent of his pitches for strikes. He’s still got some projection and has time to recover, but at some point we’ll have to concede the stuff is what it is … Their sixth-round pick from 2022, Josh Hood can hit a fastball — but not much else — with 50/55 power, and he can move between second, third, and short, enough to be a utility infielder if he starts hitting anything with a wiggle … Outfielder Alberto Rodriguez was designated for assignment in January, but cleared waivers and was outrighted to Tacoma. He had a bad year in 2022, hitting for less contact and less power, but he’s just 22 this year and was a victim of the roster rules, as he had to go on the Mariners’ 40-man roster shortly after his 21st birthday, when he had barely 200 games of pro experience. I’m not writing him off yet … Shortstop Martin Gonzalez signed for $1.5 million last January, but the Dominican infielder struck out 40 percent of the time in his debut in the DSL.

2023 impact

There aren’t any job openings in Seattle at the moment, which is probably fine given how far away most of their best prospects are. Then almost has to debut this year if he’s healthy, and I imagine Miller or Hancock will get the call if they need a spot starter during the season.

The fallen

Right-hander Sam Carlson worked so hard to come back from Tommy John surgery and other arm problems, pitching a little in the last two years in Low-A Modesto, but the Mariners’ second-round pick in 2017 is probably never going to make it. I take no pleasure in reporting this.


Michael Arroyo might end up the best Arroyo in the system a year from now. I don’t love projecting that quickly on DSL guys, but he’s got the eye and such a good swing that I’ll do it here.

(Photo of Harry Ford: Larry Goren / Four Seam Images via AP)

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