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The arrival of the offseason means that it's time to rank stuff. Already this winter, we've sized up the 60 best free agents, both on an overall and positional basis. There's no law that prevents us from ranking minor-league players in addition to their big-league counterparts. As such, we're going to spend the winter evaluating every team's farm system. 

The lack of a minor-league season makes that more of a challenge this year. It doesn't help that some teams opted against sharing video and data from their alternate-site camps with the rest of the league. As such, we've opted against overthinking this. Our rankings will essentially be the same as they were last winter with a few changes. First, we'll exclude anyone who graduated by exhausting their rookie eligibility; second, we'll replace them with draftees or other worthy prospects; and third, and lastly, we'll present the information in a new format.

In every article in this series, you'll find a team's top five prospects as well as five others we felt like including, either because of their promise or some other reason. For those top five prospects, you'll find a quick summation of their pros (their saving grace, if one will) and their cons (their fault line), as well as beefier report and our attempt to peg their "likeliest outcome."

These rankings were compiled by talking to industry folks -- scouts, analysts, and other evaluators -- and include a touch of our own evaluative biases. Remember, that this is more of an art than a science, and that the write-ups matter more than the rankings themselves.

Now, let's get on to the top five prospects in the Seattle Mariners system.

1. Jarred Kelenic, OF

Age (as of 4/1/2021): 21

Height/Weight: 6-foot-1, 190 pounds

Acquired: Part of the Robinson Cano trade (Mets)

Highest level: Double-A

Saving grace: Precociousness and offensive potency

Fault line: Defensive value in center

Scouting report: Kelenic probably would've made his big-league debut in 2020 with a normal season. Alas, he'll have to wait until 2021. Kelenic has the means to make up for lost time; he's an advanced hitter who should contribute across the triple-slash categories. He has a simple, in-control swing that nonetheless permits him to generate easy, above-average power. Kelenic isn't going to win a Gold Glove in center field, in all likelihood, but he's playable there and may improve. As an added bonus, he should be able to steal a handful (or two) of bases a year as well. 

Likeliest outcome: Bat-first center fielder

2. Julio Rodriguez, OF

Age (as of 4/1/2021): 20

Height/Weight: 6-foot-3, 180 pounds

Acquired: International amateur free-agent signing (Dominican Republic)

Highest level: High-A

Saving grace: Precociousness and offensive potency

Fault line: Defensive value

Scouting report: Rodriguez will almost certainly be the top prospect in the system this time next year. He has the makings of becoming a middle-of-the-order fixture who hits for average and big-time power alike thanks to his bat speed, strength, and feel for making loud contact. Rodriguez split the 2019 season between A- and High-A and, despite being several years younger than his competition, hit .326/.390/.540 in what was his stateside debut. Defensively, he's likely heading for permanent residence in right field, where his well-above-average arm should help him atone for whatever range he may lose in time as he adds weight to his frame. 

Likeliest outcome: Prototypical starting right fielder

3. Logan Gilbert, RHP

Age (as of 4/1/2021): 23

Height/Weight: 6-foot-6, 225 pounds

Acquired: No. 14 pick in the 2018 draft (Stetson University)

Highest level: Double-A

Saving grace: Polish

Fault line: Out pitch

Scouting report: The Mariners have taken a collegiate starter in each of the last three drafts. Gilbert, at present anyway, appears to be the closest to the majors. He closed the 2019 season with nine Double-A starts, during which he amassed a 2.88 ERA and a 3.73 strikeout-to-walk ratio. Gilbert has an inning-eating frame to go with a good fastball and three secondary pitches that fluctuate between average and slightly above or below. With a touch more consistency, he could take a step forward. Whatever the case, he's likely to debut in 2021.

Likeliest outcome: Mid-rotation starter

4. Emerson Hancock, RHP

Age (as of 4/1/2021): 21

Height/Weight: 6-foot-4, 213 pounds

Acquired: No. 6  pick in the 2020 draft (Georgia)

Highest level: NCAA

Saving grace: High floor

Fault line: Moderate ceiling

Scouting report: Hancock was the third collegiate pitcher to come off the board in June, behind Max Meyer and Asa Lacy. There's no shame in that, though it speaks to the nature of his profile that other teams opted for pitchers with upsides that were perceived to be higher. Hancock is a strikethrower with three above-average average or better secondary offerings, making it easy to foresee him latching on as a No. 3 starter with minimal development. There are some within the game who believe there's additional upside to unlock with Hancock's arsenal. If that proves to be the case, he might end up as a No. 2 starter -- and a relative steal.

Likeliest outcome: Mid-rotation starter

5. George Kirby, RHP

Age (as of 4/1/2021): 23

Height/Weight: 6-foot-4, 215 pounds

Acquired: 20th pick in the 2019 draft (Elon University)

Highest level: Low-A

Saving grace: Precision

Fault line: Out pitch

Scouting report: Here's how stellar Kirby's control is: he walked six batters in 111 combined innings between the minors and college back in 2019. Six … out of 438 batters faced. Absurd. Kirby isn't a soft-tosser who has to nibble to make a living, either. He can get his fastball up into the upper-90s, and he has an assortment of average-ish secondary offerings (though none stand out yet as a putaway pitch). Kirby's command should enable him to play beyond his raw stuff anyway, suggesting that he could be a quick-moving mid-rotation starter -- and perhaps more if he can develop a better swing-and-miss secondary pitch.

Likeliest outcome: Mid-rotation starter

Five others to know

Trammell was involved in a deadline deal for a second consecutive year, this time shipping up to Seattle from San Diego as part of a seven-player trade. In the past, talent evaluators have compared him to Brett Gardner, which is to say he'd be a defensive asset in left field who made his money at the plate by reaching base. These days, there's skepticism about his ability to make adjustments. Maybe that proves to be unfair, but Trammell is at risk of losing his prospect shine.

Originally a third-round pick, Raleigh was able to reach Double-A in his first full professional season. It's at least conceivable that he could've made his big-league debut this year under normal circumstances. Ah, well. Raleigh has above-average raw power and enough mitt to stick behind the plate. His strikeout rate spiked upon reaching Double-A, so keep an eye on that if you want to determine whether or not he's going to have enough stick to be more than a backup.

Marte, who signed with the Mariners the July after they inked Rodriguez and who turned 19 in October, will probably crack the top five next winter, after he's (presumably) made his stateside debut. He has the potential for average or better tools across the board, including a few plus grades (power, speed, arm) that could push him closer and/or into star-caliber territory. 

Jerry Dipoto might find himself singing along with Lukas Nelson when the latter wonders why he can't save himself a little heartache by getting things right the first time -- at least when it comes to Then, who Dipoto dealt away only to reacquire a year-and-a-half later. Then's lively arm holds the promise of something real, though it's unclear at present if that something will come as a back-end starter or as a reliever. He should help fill in the blanks over the coming year.

  • Zach DeLoach, OF

The Mariners popped DeLoach with the first of their two second-round picks. He improved his stock by hitting .353/.428/.541 in the previous summer's Cape Cod League, and then by homering six times in 18 games before the season was shuttered. That last part doesn't seem like a huge deal, except that DeLoach's previous career-high in home runs was five. The Mariners must believe there's more juice in his bat than previously assumed.