January chugs along and that can mean only one thing around these parts: it’s time to rank minor-league prospects. Every team across the majors is selling hope to their fans: some are selling it in a more immediate fashion, in the form of active offseasons full of free-agent signings and trade acquisitions. Others, meanwhile, are selling it in the personage of prospects who could make the difference over the coming years.
CBS Sports is underway examining the top three prospects in each organization. Our definition of “prospect” is simple: does that player have rookie eligibility remaining for the 2025 season? If so, they’re a prospect; if not, that’s probably why your favorite young player is absent from the proceedings.
As always, these lists are formed following conversations with scouts, analysts, player development specialists, and other talent evaluators around the industry. There’s a fair amount of firsthand evaluation, statistical analysis, and historical research mixed in, too. Plus a heaping of personal bias — we all have certain traits and profiles that we prefer over others, there’s no sense pretending otherwise.
Keep in mind that there’s no one right answer with these sorts of things. Besides, these are merely our opinions, meaning they have no actual bearing on the future. We already published our ranking of the top 25 prospects in all of the minors.
With all that out of the way, let’s get to ranking the top three prospects in the Seattle Mariners system.
Top 25 rank: No. 7
The short hook: Polished lefty-hitting shortstop
Emerson had scouts swooning in the spring. He made good on that preseason hype during the year, impressing in both the California and Arizona Fall Leagues while scuffling in the Northwest League to round out his regular season. It’s hard to get too worked up about the latter experience; he was nearing the end of his first full year as a professional (a season that contained multiple trips to the injured list, mind you), and he was playing in leagues as a teenager that featured pitchers several years older. What’s important here is that Emerson projects as an above-average lefty-hitting shortstop who just needs to tap into his raw power during games. If he can do that, he’ll become a foundational piece of the Mariners’ long-term plans. MLB ETA: Summer 2026
The short hook: Potential middle-of-the-order fixture
Montes is a massive left-handed hitter, listed at 6-foot-3 with room to fill out, who won’t celebrate his 21st birthday until October. That’s notable since he split last season between Low- and High-A, outperforming the league-average marks by 25% or or more against competition that was several years his senior. Montes’ calling card is his well-above-average strength. He’s already shown the ability to exit the ballpark to left- and right-center, and there’s every reason to believe he’ll feature pole-to-pole power by the time he’s fully developed. Montes did see his strikeout rate leap by 10 percentage points after his promotion to High-A. It’s reasonable to think that he’s always going to have a swing-and-miss component to his game, and combining that with his willingness to work counts will make him prone to punchouts. The Mariners won’t say boo provided he makes good on his promise of launching 30-plus homers a season. MLB ETA: Late summer 2026
The short hook: Future leadoff hitter in the making
Young is another polished left-handed hitter, albeit one who produced at an above-average clip during his season in Double-A. He relies heavily on singles and walks, and his in-game power seems likely to be contained in the form of doubles to the gap (though he did lift a few balls out the other way). Young has also stolen 20 or more bases two years in a row, giving him a chance to provide more value on the basepaths. He’s all but certain to remain up the middle, with his eventual landing spot hinging in part on Emerson’s arrival. MLB ETA: Late summer 2025
