It’s Prospect Season.
Joe Doyle is the MLB Draft Director for ProspectsLive and host of the new MLB Draft Podcast ‘Over-Slot’.
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The Seattle Mariners farm system has taken a hit over the last few years with the graduations of premium prospects like Julio Rodriguez, Jarred Kelenic, George Kirby and more. While those top-end guys have moved out of prospect status, Seattle has a handful of exciting talents with upside and versatility on the horizon. From this chair, there are reasons to be bullish on what Mariners farm system may look like nationally in the very near future.
When building out boards, personally, I take bias out of the equation. I want to see athletes and projection. I want to see tools. I want to see on-field performance that is correlative to the pure, objective, unfiltered data. This framework helps to create a fair process. Avoiding national narratives and the predispositions set on players is key.
Here are the Top 50 Mariners Prospect entering the 2023 season.
NO. | PLAYER | POS | LEVEL | ETA | FV |
1 | Bryce Miller | RHS | AA | 2023 | 50 |
From this chair, Miller is the top prospect in the Mariners system for a number of reasons. His proximity to the show plays a heavy weight in my evaluative model.
Miller is set to debut this upcoming season and there’s real reason to believe he’ll find success. For me, a pitcher needs to be armed with a bat-missing fastball to be considered a premium prospect. Miller’s fastball induced an 18-percent whiff rate in 2022, more than just about every other pitcher in the organization last year. He’ll mix in a sweeping slider that flashes above average at times, as well as a changeup that could prove effective against left-handed bats. There’s also an upper-80s cutter in there that will be useful if he hopes to chew through opposing lineups more than twice as a pro.
Miller has No. 3 starter upside and it wouldn’t surprise me if he’s one of the big storylines in Seattle this summer.
NO. | PLAYER | POS | LEVEL | ETA | FV |
2 | Harry Ford | C | A | 2025 | 50 |
Ford can really hit and I think the power might be sneakier than some think. There’s a stretch goal here of a .275 hitter who posts a few 20-homer seasons in his career. He projects an above average hitter who posts impressive on-base numbers as well. While the tools behind the plate continue to mature, he may never be strong enough back there to warrant a starting job. Ford could move to second base or into the outfield in 2023 or 2024 if the bat proves too valuable to hold back.
NO. | PLAYER | POS | LEVEL | ETA | FV |
3 | Felnin Celesten | SS | R | 2026 | 50 |
Fellow shortstop Cole Young received plenty of thought here, but Celesten gets the nod. At the end of the day, we’re talking about a true shortstop who figures to stick at the position. That means a great deal to me. Celesten has loud tools across the board and could be a quick-mover if the hit tool proves to be as polished as Seattle seems to think it could be.
I like a prospect who can see certain tools fail or regress with age and physical maturation whilst still finding success. Even if Celesten slows down, moves off shortstop or doesn’t hit for power, he has many avenues he can take to become a big-league regular. This is without question the highest ceiling of any player in the organization right now.
NO. | PLAYER | POS | LEVEL | ETA | FV |
4 | Cole Young | SS | A | 2025 | 45+ |
Cole Young can really, really hit. That hit tool will be paramount in reaching his ceiling of a big league regular. The tools at shortstop aren’t sexy, but the footwork is clean and he possesses a strong first step on the dirt. Ultimately, I think Young is moved off the position in favor of a more premium defender. That said, he has the tools to become a Joey Wendle/Jeff McNeil-esque second baseman.
NO. | PLAYER | POS | LEVEL | ETA | FV |
5 | Emerson Hancock | RHS | AA | 2023 | 45 |
Emerson Hancock is a tough pitcher for me to grade. He’ll sit 92-95 mph, touching 97, but his fastball didn’t perform well and doesn’t miss a whole lot of bats. His control for the pitch is sublime, but he may be living inside the zone a little too much for my liking. In a perfect world, Hancock would throw his four-seamer more often to take advantage of his release height, but that may be too taxing on the body and the pronation requirements at release to really make it a weapon.
At the end of the day, Hancock may end up a two-seam/changeup/slider guy who doesn’t miss a ton of bats but admirably fills a No. 4 or No. 5 spot in a rotation. Jury is still out on this one. He could surprise in 2023.
NO. | PLAYER | POS | LEVEL | ETA | FV |
6 | Gabriel Gonzalez | OF | A | 2026 | 45 |
What Gabriel Gonzalez was able to accomplish as an 18-year-old in Modesto in 2022 cannot be understated. The bat-to-ball skills exhibited here are pretty special. While I don’t love the body, I do think Gonzalez has a shot to be a bat-over-everything type of corner outfielder who makes it to the big leagues as a 21-year-old. He really reminds me of Kole Calhoun.
NO. | PLAYER | POS | LEVEL | ETA | FV |
7 | Bryan Woo | RHS | A+ | 2024 | 40+ |
Seattle is very high on Woo and it’s easy to see why. Everything about his operation on the mound screams starting pitcher. Woo has the balance, tempo and athleticism on the mound necessary to start. The stuff is big, too. The fastball touched 99 mph this season and his changeup flashes plus, though command can be spotty. If there’s a critique, Woo possesses well-below-average spin rates on his slider. He does offset that by throwing the pitch 84-86, but I do have concerns over the eventual effectiveness of his breaking ball at the highest level. If Woo can get it to the point of being even an average offering, he’d be three spots higher on this list.
Woo has the potential for two plus pitches and if he can get the spinner to even average, he has the upside of a mid-rotation starter with bat-missing stuff.
NO. | PLAYER | POS | LEVEL | ETA | FV |
8 | Michael Arroyoo | 3B | R | 2026 | 40+ |
The reports out of the Dominican last summer were very loud for Arroyo with scouts lauding the hit tool and his ability to move on the dirt. Arroyo has done a great job to this point of staying lean and playing shortstop in pro ball. He’s still a likely candidate to move to second base or third base as he matures, but his early work ethic is encouraging.
Still, the bat will dictate how quickly he moves and his eventual ceiling. All signs point to a pretty impressive hitter here.
NO. | PLAYER | POS | LEVEL | ETA | FV |
9 | Taylor Dollard | MLRP | AA | 2023 | 45 |
For me, the jury is still out on Taylor Dollard as a legitimate starting pitcher option for the Seattle Mariners moving forward. The slider is legit with plus sweeping action, and he gets a ton of depth on his curveball too. But Dollard doesn’t miss a ton of bats and the fastball is average at best. For me he is more of a mid-leverage reliever who can handle a spot-start when needed. The Penn Murfee comparisons aren’t totally fair as Murfee lives off deception and tunneling. Dollard lives off soft contact and manipulating the baseball. He’ll prove valuable for Seattle very soon, but likely won’t ever be a guy who posts north of 100 innings in a season at the highest level.
NO. | PLAYER | POS | LEVEL | ETA | FV |
10 | Prelander Berroa | HLRP | AA | 2023 | 40+ |
For me, Berroa is a reliever. Simple as that. The fastball command isn’t there right now to project anything more. But anytime you’re talking about a guy who can touch triple digits and compliment it with a legitimate double-plus bat-missing slider, you have a valuable asset.
I’ve always graded leverageable relief prospects fondly as I think it’s the market inefficiency in prospect grading. Berroa figures to debut in 2023 for Seattle and could be used in tight spots almost immediately.
NO. | PLAYER | POS | LEVEL | ETA | FV |
11 | Axel Sanchez | SS | A | 2026 | 40+ |
Sanchez was a dynamo at Modesto in 2022, though he was streaky and the sample size wasn’t robust. Sanchez can get pretty trigger-happy at the plate and that has a tendency to bloat his strikeout rates. He needs to show a more consistent approach at the plate in 2023 if he hopes to continue his climb up boards and prove the hit tool is a legitimate weapon. Showing more of the thump he teased next year also wouldn’t hurt his projection.
He has the tools necessary to stick at shortstop and he’ll be 20 years old in 2023. He is likely to begin the season at Modesto once again and should remain there until the hit tool shows more polish.
NO. | PLAYER | POS | LEVEL | ETA | FV |
12 | Tyler Locklear | 1B | A | 2025 | 40 |
Going back to his college days, Locklear has always been one of the best pure hitters in whichever league he’s playing, and in just about every category. He limits strikeouts, bludgeons the baseball, takes walks, and doesn’t chase.
After a slow start, he finished with a flurry in Modesto. Locklear will be challenged in 2023 and will see much better stuff in Everett and potentially in Arkansas later this summer. Coming from mid-major Virginia Commonwealth, he hasn’t been exposed to much truly premium stuff. This season will be a barometer for just how far along the development spectrum he is.
There is the potential for a solid average hit tool here with plus, maybe even double-plus power. Think: CJ Cron.
NO. | PLAYER | POS | LEVEL | ETA | FV |
13 | Lazaro Montes | OF | R | 2027 | 40 |
Montes was the big fish in Seattle’s 2022 international signing class, netting $2.5 million, the largest international bonus ever dolled out oby Seattle at the time. He showcased the big power most expected, smacking 10 homers in 55 games, though the swing-and-miss was a bit heavier than most expected.
Montes fanned in over 33 percent of his plate appearances; a bit of an alarming figure for a bat-first prospect.
Despite the team suggesting he could play centerfield as a pro, Montes did not play an inning up the middle in 2022, instead playing almost exclusively in right field when he wasn’t the designated hitter.
Montes will have to show an improved approach and improved bat-to-ball skills in 2023 should he hope to continue climbing boards. The god-given tools are fairly obvious.
Polish is the next checkbox. At this time, he projects a bit like ex-Mariners outfielder Carlos Peguero.
NO. | PLAYER | POS | LEVEL | ETA | FV |
14 | Walter Ford | RHS | R | 2026 | 40 |
The self-proclaimed “Vanilla Missile” will take the mound for the first time in affiliated ball in 2023 and scouts are excited to see what he brings to the bump. Ford will be 18 years old for the entire 2023 campaign, but his stuff far exceeds that of a teenager. At his best, Ford can rush it up into the upper-90s with a devastating sweeping slider. He also flashed a curveball with tremendous two-plane break.
Ford is a terrific athlete with substantial projection remaining. Control and command were a bugaboo for Ford at times during his senior year in high school. That’ll be a big barometer for just how far along the development spectrum he actually is this season.
Ford will likely see Modesto this season, but may start the year at the Arizona Complex League.
NO. | PLAYER | POS | LEVEL | ETA | FV |
15 | Cade Marlowe | OF | AAA | 2023 | 40 |
Marlowe lands here due to proximity and his potential to immediately impact the big league club. Marlowe is more tooled-up than many give him credit for, with a smattering of average tools, though the swing-and-miss in his game has scouts wondering whether he’ll hit enough to reach his big-league regular ceiling.
If Marlowe gets the at-bats, he has the chance to be a guy who hits 15 homers and steals 15 bags for the club, though he’ll have to earn those opportunities whilst likely being provided limited opportunities at the plate early in his career.
NO. | PLAYER | POS | LEVEL | ETA | FV |
16 | Jonatan Clase | OF | A | 2024 | 40 |
This coming season will surprisingly be Clase’s sixth year in the Mariners organization, yet he won’t turn 21 until late May. For as long as he’s been a prospect, he’s still incredibly young, but he does still have much to prove.
Clase is a burner and will without question be a valuable asset on the basepaths for Seattle at some point in the future, maybe as early as late-2023 in late-inning situations. Clase showed an improved hit tool in 2022 whilst also flexing the muscle a bit running into 13 homers. Clase will likely start 2023 at High-A Everett.
If the bat shows mature enough to move him up to Arkansas at any point, a September call-up wouldn’t be out of the question, especially as he’s already on the 40-man roster. He still profiles a Brett Gardner type of table-setter.
NO. | PLAYER | POS | LEVEL | ETA | FV |
17 | Michael Morales | MLRP | A | 2026 | 40 |
When Seattle drafted Morales in the third round in 2021 — poaching him away from a Vanderbilt commitment — it was all about patience and projection. A lot of Morales’ appeal is what it could become. His fastball features some hop and arm-side run, but it presently sits 90-92. His curveball is a bit generic presently, but with added strength and maturation, it could play up as its velocity increases. There’s a slider in there too, but its shape is inconsistent.
Morales does, however, have a good feel for the strike zone with it. The changeup might be his best weapon right now with considerable arm speed and conviction, as well as darting action. It could be an above average offering with time.
Without a velocity spike, Morales projects as a back-of-the-rotation strike-thrower. If the projection card hits, he could work his way into a mid-rotation, reliable starter with four average-or-better pitches.
NO. | PLAYER | POS | LEVEL | ETA | FV |
18 | Isaiah Campbell | MLRP | AA | 2023 | 35+ |
Finally healthy, Isaiah Campbell’s stuff took a huge step in the right direction in 2022 pitching out of the bullpen. He now projects a legitimate big-league weapon late in games. Up to 98 mph last season, Campbell rests 93-95 featuring significant two-plane bite. His fastball missed a ton of bats last season. In fact, with a 48-percent isolated whiff percentage, Campbell’s fastball actually missed more bats than anyone else’s fastball in the entire organization last year. And by a wide margin.
The heater was his most effective pitch, but Campbell also flashed an above-average slider with above-average spin rates and showed real feel for commanding the pitch. He’ll throw the occasional curve and changeup, though both pitches lag behind his two primary weapons. Campbell is likely to eat some mid-leverage innings out of the Seattle bullpen in 2023.
NO. | PLAYER | POS | LEVEL | ETA | FV |
19 | AJ Izzi | RHS | R | 2026 | 40 |
Izzi is a long, wiry pitching prospect who figures to add quite a bit of muscle and strength as he matures. At 6-foot-3, 175 pounds, Izzi is already touching 94 mph and could find his way into the upper-90s in a relief role.
He’s got a lightning quick arm and presents impressive athleticism on the mound. The heater has some deception and hop late in the zone. A splitter/changeup is his most polished secondary with some fade off his fastball tunnel. The slider is short, but Izzi has a tendency to broadcast the pitch.
There’s some effort in the delivery here with notable head-whack at release. Izzi’s most likely outcome is in the bullpen where he may be able to let the fastball eat and supplement it with a couple average secondaries.
NO. | PLAYER | POS | LEVEL | ETA | FV |
20 | Robert Perez Jr. | 1B/OF | A+ | 2024 | 35+ |
Perez Jr. really improved his stock as a prospect in 2022, launching 27 homers across two levels, culminating in a strong 35-game stretch to end the season in High-A Everett. Perez Jr. showed a decent bit of swing-and-miss in his time at Modesto, but brought that down to a rather healthy level after the move up to Everett late in the season.
This season will be a big campaign for the Venezuelan first-base prospect. If he can show the approach and value with the bat over a longer sample at Everett and potentially Arkansas, Perez could be in line to debut with Seattle in 2024. He doesn’t provide much value outside of the bat, but he’s making the case it may be valuable enough alone.
NO. | PLAYER | POS | LEVEL | ETA | FV |
21 | Spencer Packard | OF | A+ | 2024 | 35+ |
Packard was limited by injuries in 2022, but when healthy provided significant thump and impact to a High-A Everett lineup that lacked it for much of the year.
At his best, Packard is an above-average hitter with a discerning eye at the plate. He rarely strikes out and draws a fair number of walks as well. He’s shown above-average raw power, and he’s getting to most of it in games too.
Packard is fringy in the outfield corners, has a fringy arm, and doesn’t provide a ton of value in the field. At 25, he’lll need to stay on the field this season and should see Arkansas at some point. He’s on a similar track as Marlowe and could present himself a tricky Rule 5 option at the end of the 2023 season.
Packard projects as a fourth outfielder at the next level, though the bat could be polished enough to warrant some starts at DH.
NO. | PLAYER | POS | LEVEL | ETA | FV |
22 | Alberto Rodriguez | OF | A+ | 2025 | 35+ |
It was a step back in 2022 for Alberto Rodriguez who saw his contact percentage drop, his chase percentage jump, and his overall production take a hit. Rodriguez also showed less impact on the basepaths. After showing off a leaner, more physical body in 2021, Rodriguez’ frame seemed to revert back a bit last season.
Ultimately, this looks like a left-field profile with fringy tools scattered about his scouting report. The hit tool will need to resurface up into 2021 levels if he hopes to continue climbing the organizational ladder.
Rodriguez was DFA’d in January, removing him from the 40-man roster. That may ultimately be a good thing for his development as it takes some pressure off the idea of having to rush him to the big leagues. Just 22 years old, Rodriguez and the organization can take their foot off the proverbial pedal and take things slow in 2023.
NO. | PLAYER | POS | LEVEL | ETA | FV |
23 | Juan Mercedes | MLRP | A+R | 2025 | 35+ |
This will be year seven for Mercedes with the Mariners. He will play out this season at the age of 23.
Up to 94 mph, Mercedes will sit in the low-90s with his fastball, though it features generic shape and struggles to miss bats. His best pitch is a sweeping slider that he’s shown tremendous control of and a willingness to use consistently. The changeup may be his best secondary in terms of pitch shape as it features tons of arm-side fade and has been a weapon against left-handed hitters.
Without significant changes to his fastball profile or added stuff, Mercedes is likely an up-and-down arm who can eat multiple innings in a pinch. His stuff isn’t quite leverageable at this stage, though the slider does have some teeth.
NO. | PLAYER | POS | LEVEL | ETA | FV |
24 | Juan Pinto | MLRP | R | 2026 | 35+ |
Pinto, a member of the Mariners 2021 international free agent class, will spend almost all of the 2023 season at 18 years of age. The 6-foot-3-inch lefty has added close to 30 pounds to his frame since joining the organization and now has the fastball up to 92 mph.
His best secondary is a curveball that flashes plus potential, though Pinto’s entire repertoire is held back by well below-average control. Pinto walked 29 batters in 30.1 innings as a 17-year-old at the Dominican Summer League last season. Scouts believe he could end up a player similar to Roenis Elias in due time.
NO. | PLAYER | POS | LEVEL | ETA | FV |
25 | Tyler Gough | LLRP | R | 2026 | 35+ |
The Mariners liked what they saw in Gough at the MLB Draft Combine prior to the 2022 Draft and are excited about what’s to come in 2023 when Gough takes the mound for the first time professionally. Gough will focus on getting more physical and athletic as he develops in the Mariners system. At his best in his prep days, Gough touched 97 mph, though he’d sit in the low-90s in longer outings, flashing a slider/changeup combo that were effective in showcase settings.
NO. | PLAYER | POS | LEVEL | ETA | FV |
26 | Jean Munoz | MLRP | R | 2025 | 35+ |
The Mariners inked Munoz during the 2019 international signing period and his stuff has really exploded ever since. Now 20 years old, Munoz is touching 95 mph, resting a couple ticks below that over extended outings. Not yet deployed as a reliever, it is believed Munoz could be sitting in the upper 90s when the training wheels come off out of the bullpen.
He also throws a firm breaking ball that sits in the low-80s. The shape of both his fastball and breaking ball have a ways to go in terms of consistency and polish, but in time Munoz could develop into a mid-or- high-leverage arm.
NO. | PLAYER | POS | LEVEL | ETA | FV |
27 | Zach DeLoach | OF | AA | 2024 | 35+ |
When the Mariners drafted DeLoach in the second round in the 2020 draft, they probably expected a bit more production than what they’ve seen to this point. He was a solid yet unspectacular in 2022.
He exhibited more of his trademark keen eye at the plate, drawing tons of walks, but his strikeout rate remained steady at ~24 percent. When coupled with his lack of game power and his lack of physical and athletic tools on the basepaths and in the field, DeLoach more and more projects an up-and-down 26th guy off the bench.
Still just 24 years old, there’s still time for the polished outfielder to get more physical at the plate or improve his hit tool. Until one of those two things happen, he profiles more a Quad-A regular rather than a big leaguer.
NO. | PLAYER | POS | LEVEL | ETA | FV |
28 | Chris Clarke | MLRP | AAA | 2023 | 35+ |
Come spring training, Clarke may not even be on the team given the requirement to keep him on the active big league roster all season. For the time being however, his profile is intriguing. Clarke will work up into the mid-90s with heavy sink and a steep approach angle.
He’ll break a lot of bats with the heater, and should be a ground ball machine. Couple this with a true downer curveball and above-average command and Clarke projects a guy who could make a spot start or handle a multi-inning workload if the team needed it, especially early in the season as starters are ramping up.
Clarke’s unique pitch traits and versatility could prove valuable, though he likely won’t ever exceed his mid-leverage bullpen ceiling.
NO. | PLAYER | POS | LEVEL | ETA | FV |
29 | Hogan Windish | 2B | A | 2025 | 35+ |
There wasn’t another player in the 2022 draft — league-wide — who got as much experience as Windish did last summer. After being selected in the seventh round, the Mariners got Windish 157 professional plate appearances, most of those in Modesto.
The biggest knock on Windish’ prospect sheen is his age, as 2023 will be his age-24 season. Still, Windish was a base-hit machine at UNC-Greensboro and continued his hitterish ways for Seattle last summer.
He’s limited defensively, likely a below average defender at second base or an average glove at first base. Most scouts do not believe he has the arm for third base.
The bat will need to do yeoman’s work for Windish to reach his big- league ceiling. There’s the potential here for an above average hit tool. Windish actually possesses above-average raw power, maybe even a tick more, but he’s still working to incorporate all of it into games. He has had a propensity to hit the ball on the ground a lot.
NO. | PLAYER | POS | LEVEL | ETA | FV |
30 | Travis Kuhn | MLRP | AA | 2023 | 35+ |
Kuhn has battled injuries the last couple years, but when on the bump, he’s showcased some unpolished big -eague stuff. In 2022, Kuhn touched 99 mph and sat 95-97 with authority. It’s a bit of a vanilla 99, if that exists, so Kuhn struggled to miss bats with the heat.
That, coupled with inconsistent command, really capped his production. Kuhn also offers a hard, short slider that plays off his fastball, though it lacks the movement profile necessary to project anything more than an average offering presently. He’ll need to continue refining the shape of his fastball and keep it in the zone if he hopes to reach his mid-leverage bullpen ceiling.
NO. | PLAYER | POS | LEVEL | ETA | FV |
31 | Dylan Wilson | RHS | R | 2028 | 35+ |
NO. | PLAYER | POS | LEVEL | ETA | FV |
32 | Josh Hood | 3B | A | 2025 | 35+ |
NO. | PLAYER | POS | LEVEL | ETA | FV |
33 | Jeter Martinez | RHS | R | 2027 | 35+ |
NO. | PLAYER | POS | LEVEL | ETA | FV |
34 | Yeury Tatiz | MLRP | A | 2024 | 35+ |
NO. | PLAYER | POS | LEVEL | ETA | FV |
35 | Roiber Talevara | MLRP | R | 2026 | 35+ |
NO. | PLAYER | POS | LEVEL | ETA | FV |
36 | Starlin Aguilar | 1B/3B | R | 2026 | 50 |
NO. | PLAYER | POS | LEVEL | ETA | FV |
37 | Carlos Jimenez | CF | R | 2026 | 35+ |
NO. | PLAYER | POS | LEVEL | ETA | FV |
38 | Jimmy Joyce | LLRP | A+ | 2025 | 35+ |
NO. | PLAYER | POS | LEVEL | ETA | FV |
39 | Victor Labrada | CF | A | 2024 | 35+ |
NO. | PLAYER | POS | LEVEL | ETA | FV |
40 | Darren Bowen | LLRP | R | 2026 | 35+ |
NO. | PLAYER | POS | LEVEL | ETA | FV |
41 | Kendal Meza | MLRP | R | 2027 | 35+ |
NO. | PLAYER | POS | LEVEL | ETA | FV |
42 | Milkar Perez | 1B/3B | A | 2026 | 35+ |
NO. | PLAYER | POS | LEVEL | ETA | FV |
43 | Logan Rinehart | LLRP | A+ | 2024 | 35+ |
NO. | PLAYER | POS | LEVEL | ETA | FV |
44 | Martin Gonzalez | SS | R | 2026 | 50 |
NO. | PLAYER | POS | LEVEL | ETA | FV |
45 | Kaden Polcovich | 2B | AA | 2024 | 35+ |
NO. | PLAYER | POS | LEVEL | ETA | FV |
46 | Aneury Lora | MLRP | R | 2026 | 35+ |
NO. | PLAYER | POS | LEVEL | ETA | FV |
47 | Gabe Moncada | 1B | A | 2026 | 35+ |
NO. | PLAYER | POS | LEVEL | ETA | FV |
48 | Juan Then | LLRP | AA | 2024 | 35+ |
NO. | PLAYER | POS | LEVEL | ETA | FV |
49 | Jorge Benitez | LLRP | A+ | 2025 | 35+ |
NO. | PLAYER | POS | LEVEL | ETA | FV |
50 | Tatem Levins | C/1B | R | 2026 | 35+ |
Joe Doyle
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- JOE DOYLE: Top 50 Mariners Prospects - January 31, 2023