Below is an analysis of the prospects in the farm system of the Seattle Mariners. Scouting reports were compiled with information provided by industry sources as well as my own observations. This is the fifth year we’re delineating between two anticipated relief roles, the abbreviations for which you’ll see in the “position” column below: MIRP for multi-inning relief pitchers, and SIRP for single-inning relief pitchers. The ETAs listed generally correspond to the year a player has to be added to the 40-man roster to avoid being made eligible for the Rule 5 draft. Manual adjustments are made where they seem appropriate, but we use that as a rule of thumb.
A quick overview of what FV (Future Value) means can be found here. A much deeper overview can be found here.
All of the ranked prospects below also appear on The Board, a resource the site offers featuring sortable scouting information for every organization. It has more details (and updated TrackMan data from various sources) than this article and integrates every team’s list so readers can compare prospects across farm systems. It can be found here.
Other Prospects of Note
Grouped by type and listed in order of preference within each category.
Working Back From Injury
Cole Phillips, RHP
Taylor Dollard, RHP
After sitting about 91 mph in the summer after his junior year, Phillips was sitting 94-98 with relative ease during his draft spring until he had Tommy John in early April. The Braves still saw fit to give him about $1.5 million in the second round. The Mariners used their amateur reports to inform their decision when they traded for Phillips as part of the Jarred Kelenic/Evan White contract swap. Phillips needed a second Tommy John before the 2024 season, and then had a stress reaction in his elbow that has shelved him for all of 2025 so far. He has yet to throw a single pro pitch in an actual game, and is on pace to return in August. It’s tough to give him a main list FV at this point, but he’s a high-priority target for scouting during Bridge League/instructs. Dollard is coming off rehab for surgery to repair a torn labrum and is only sitting in the upper-80s through about a half-dozen appearances since his return. At peak, he looked like a pitchability backend starter.
Fringe Hitters
Jared Sundstrom, OF
Bill Knight, CF
Rhylan Thomas, OF
Milkar Perez, 1B
Austin St. Laurent, INF
Victor Labrada, OF
Sundstrom is an athletic 23-year-old power/speed outfield prospect from UC Santa Barbara. He’s playing mostly right field, and is another hitter in this org whose swing leaves him vulnerably tardy on the outer third. Knight is a 40-hit/30-power guy who can really play center field. The 25-year-old is at Arkansas and has a 102 wRC+ after posting a 94 at Everett last year. Thomas is a slender, tough-to-K corner outfielder out of USC who is a career .300 hitter in the minors. He had his first big league cup of coffee in 2025 and is a fine upper-level depth option. Perez is a 23-year-old Nicaraguan first baseman who could have run for Mayor of Modesto after his third full-season assignment there last year. He has finally reached Everett and is making a plus rate of contact from the left side. He’s a smaller guy without typical first base pop. St. Laurent was a 2024 Day Three pick who is off to a good start with the bat at Modesto. He has a short, downward-cutting swing that produces a ton of oppo contact. Labrada is high-motored, plus-plus running left fielder who seems to have made some adjustments at Double-A and is striking out much less so far in 2025. He has fifth outfielder ceiling.
Ex-Two-Way Guys and Conversion Arms
Sauryn Lao, RHP
Hagen Danner, RHP
Grant Knipp, RHP
Lao, 25, was a third baseman in the Dodgers system and converted in 2022. Danner, 26, was a two-way prospect in high school who began his pro career as a catcher before he moved back to the mound and has been toiling away at Triple-A since 2023. Both are mid-90s guys with sliders. Lao’s is great, but his fastball plays down, while Danner’s stuff has been average for a little while now. Knipp was a two-way player at Campbell who touched 100 at the 2024 Combine. He had TJ just before the 2025 season. Realistically, he’s an eventual reliever.
Good Breaking Stuff
Blas Castaño, RHP
Michael Hobbs, RHP
Juan Burgos, RHP
Peyton Alford, LHP
Castaño was originally a Yankee but was released toward the end of the 2023 season and hopped on with the Mariners. He’s a funky low-ish slot righty with a kitchen sink (emphasis on sink) repertoire that leans on his sinker, cutter, and sweeper. He debuted this year and is an emergency depth option. Hobbs is a 25-year-old Double-A reliever who was drafted by the Dodgers, then was a Mets minor league Rule 5 pick in 2024, and then was traded to Seattle in March of 2025. He tries to sneak breaking balls into the top of the zone and then elevate a low-90s fastball above it for chase. In 2025, it’s working; he’s leading the Arkansas roster in swinging strike rate. He’s a bit too wild for a guy who sits 91 to include on the main section, but he’s definitely in the mix for emergency depth innings. Burgos is a 25-year-old Dominican reliever who’ll touch 98, albeit with ineffective movement. He pitches off his hard slider/cutter, which is above average but plays down as a bat-misser because he relies on it to do so many other things. Alford is a fun little (he’s 5-foot-8) undrafted lefty out of Virginia Tech whose 91-93 mph fastball has plus-plus vertical movement. Alford is a great athlete for his size and can snap off a nice curveball, but he’s 27 and his performance has regressed even though he’s repeating Double-A.
Funkadelic Relievers
Tyler Cleveland, RHP
Jimmy Joyce, RHP
Taylor Floyd, RHP
Cleveland is a 25-year-old submarine relief righty at High-A. His stride direction looks like Andy Petitte’s pickoff move, which has been altered since the Mariners drafted him out of Central Arkansas. He looks like a Jimmy Herget type specialist. Because I assume Joyce goes by “Jimmy” so that he isn’t bombarded with jokes about stream of consciousness prose, I’ll spare everyone mine. Joyce has a funky and deceptive low-release that he comes to via a big, open stride down the mound. His secondary pitches get big lateral action in either direction, with his changeup emerging as his weapon of choice earlier this year before he hit the IL in late April. Floyd was once a 40 FV sidearm relief prospect with uncommon arm strength for someone with his mechanics. His delivery changed seemingly by accident entering 2023, his stuff and command backed up, and he began bouncing around, from Milwaukee to Minnesota and now Seattle. He’s having a better 2025 as his slider plays like a plus pitch at Arkansas.
Uphill Heaters
Anyelo Ovando, RHP
Pedro Da Costa Lemos, RHP
Evan Truitt, RHP
A 6-foot-5, XXL righty who generates over seven feet of extension down the mound, Ovando is a 24-year-old A-ball reliever who has 40-grade stuff, but a big league frame and delivery. A 22-year-old Brazilian righty, Da Costa Lemos’ upshot, low-90s fastball is generating plus miss at Modesto. Truitt, 22, is an athletic, 6-foot righty who commands an uphill fastball and cutter. He’s throwing strikes in Everett but has been homer-prone.
Long-Term Dev Projects
Dawel Joseph, SS
Aiden Butler, RHP
Dylan Wilson, RHP
Joseph signed for $3.3 million in 2024 and had a really awful first pro season in the DSL, where he hit .133. He’s off to a K-prone start in 2025. Butler is a 6-foot-6 righty out of Polk State College in Florida who has already pitched his way off the complex and to Modesto. He’s sitting in the low-90s and his breaking balls have plus spin, but his command is pretty raw. A 6-foot 19-year-old righty from Curaçao, Wilson has a low-90s fastball, two decent breaking balls (a low-80s lateral slider and a slower, vertical curveball), and the makings of a viable splitter. He’s an above-average athlete with below-average physical projection.
System Overview
This is probably the only system in baseball that is good even though it’s shallow. It’s rare for me to write up fewer than 30 guys in an org (with the extras I wrote up a little over 50, but you get what I mean), and usually when I do, it’s a stinker. But not only is the Mariners farm system good, it’s arguably one of the best handful in baseball because it has so many potential impact bats up top. Teams are desperate for young, everyday-quality position players, and Seattle has several youngsters with that kind of ceiling. While I clearly have qualms about some of these guys, there are so many of them that it’s likely that at least a few will pan out, and that the team’s lineup three-ish years from now will be deeper and more stable than the shallow group they’re running out there right now. If that’s too long for Mariners fans/ownership to wait for true replenishment, then a player or two from this group can be traded. Potential everyday hitters move the needle in trade discussions unlike any other prospect demographic, and the Mariners might be comfortable dealing from their depth at catcher, or the middle infield, or in center in order to make something happen sooner. Their redundancy at those spots could make it less painful to part with one or two of the kids at Everett if it means landing a good hitter with multiple years of control remaining on his deal. They did this last year with Aidan Smith in the Randy Arozarena trade.
The Mariners are in this position because of their recent draft strategies, which have resulted in them adding at least one over-slot high schooler early in the selection process and then pivoting to senior signs (or other older, low-bonus players) before any of the other teams, putting them in position to take the best available seniors. Ben Williamson was one of those low-bonus guys whose lack of negotiating leverage helped the M’s bonus pool math work out in 2023, and he’s been good enough to reach the bigs. With the Mariners picking third overall this year, they may not be in a position to deploy any kind of fun or novel strategy; they might just take an obviously good player at pick three, pay him slot, and then stick to slot bonuses for the rest of the draft.
Internationally, things have been mixed. The Mariners aren’t afraid to give a huge bonus to one guy in that market, and perhaps this is part of why the org lacks overall depth. The org bet big on Dawel Joseph, and not only has he struggled to find traction in the DSL, but his signing came with enormous opportunity cost. It’s tough to have a deep international class when one guy gets $3 million or more, and when that one player doesn’t work out, it often means you punted on a whole year of potential talent cultivation.
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