Colt Emerson’s Big League Push: Mariners’ Top Prospect Turning Heads in Peoria
PEORIA, Ariz. - Colt Emerson might want to get used to life on the move. After a 2025 season that saw him bounce from Spring Training to High-A Everett, then to Double-A Arkansas, Triple-A Tacoma, and even a postseason taxi squad stint, the Mariners’ No. 1 prospect is back in Arizona-and he’s making a strong case that his next stop should be Seattle.
Ranked No. 9 overall by MLB Pipeline, Emerson isn’t just knocking on the door. He’s practically camped out on the front porch of T-Mobile Park.
“I’m just grateful to be here, honestly,” Emerson said earlier this week. “And I’m going to do my best.
At the end of camp, if I get cut, if I don’t get cut, I think I’m in a great position either way. But at the end of the day, I’m excited to compete and show the staff that I want to win really bad-and I will be a winning player, in Double-A, Triple-A, whatever level I’m at.”
That’s the kind of mindset that turns heads in a front office. But while fans and media will naturally fixate on when Emerson makes his debut, the Mariners are more focused on how and where he fits into the infield puzzle.
A Glove That’s For Real
Emerson is getting reps all over the dirt this spring-shortstop, second base, and third-continuing the positional versatility he worked on during the offseason. Shortstop remains his natural spot, and the defensive tools are legit. He’s arguably the best glove in Seattle’s No. 3-ranked farm system, flashing plus range, soft hands, and advanced footwork that’s rare for a 19-year-old.
“I like to stay as consistent as possible with everything,” Emerson explained. “But each position is different.
Third base, I’m fielding more one-hand; shortstop, it’s just more natural; and then second base, you get different steps. It’s basically the flip side of shortstop.”
For now, shortstop is locked down by veteran J.P. Crawford, who’s entering the final year of his five-year, $51 million deal.
But that doesn’t mean the Mariners are moving Emerson off the position long-term. In fact, the opposite might be true.
“When we drafted Colt, our expectation was that he would grow into a bigger body and eventually play himself off of shortstop,” said Mariners president of baseball operations Jerry Dipoto. “We don’t think that’s the case at all. He’s refined his body and became an even better shortstop.”
That’s high praise-and it’s backed up by the work Emerson’s been putting in with longtime infield coach Perry Hill. Known around the clubhouse as “Bone,” Hill has been a fixture in Mariners’ player development and has taken a hands-on role in Emerson’s defensive growth.
“You can’t get bored with fundamentals if you want to be a great player,” Emerson said, quoting Hill directly. “That’s a quote from ‘Bone.’ That’s an exact quote.”
Hill has emphasized the concept of making plays “in the box”-the 10-foot radius around an infielder’s starting position. It’s not about highlight-reel diving grabs; it’s about converting the routine plays every single time.
“The confidence in making the routine play frees me up to make the spectacular-it makes that fun,” Emerson said. “It makes that like, ‘OK, I get the opportunity to make the diving catch,’ or whatever.
And it’s such a split-second thing. But I think being ready for the routine play allows me to get the first step on a diving ball.”
The Bat Still Leads the Way
While Emerson’s glove is gaining more attention, the bat is still what headlines his prospect profile. MLB Pipeline calls him the “owner of the best hit tool in the Mariners system,” and it’s easy to see why. His swing is compact, his plate discipline is advanced, and he’s got enough juice to drive the ball gap-to-gap-even against high-end velocity.
During a recent round of batting practice on the backfields in Peoria, Emerson was locked in, unloading on the velo machine like a big leaguer prepping for Opening Day. The sound of the bat told the story: this kid can hit.
And that’s what makes him such an intriguing piece for Seattle’s roster construction. Dipoto has hinted that Emerson might be more of a “sneaky five-tool guy” than people realize. If the glove keeps pace with the bat-and early signs say it is-then the Mariners might have something special brewing.
Where He Fits in the 2026 Picture
The Mariners aren’t tipping their hand just yet. Cactus League games begin Friday, and that’s when the real evaluations begin. Emerson, a non-roster invitee, is going to get a long look-right alongside 40-man roster players like Ryan Bliss and Miles Mastrobuoni, as well as fellow NRI Patrick Wisdom.
As of now, the infield depth chart reads: Brendan Donovan at third, Cole Young at second, and Leo Rivas in a utility role. But with Emerson’s talent and versatility, he’s not just depth-he’s a potential difference-maker.
Whether he breaks camp with the big club or not, one thing is clear: Colt Emerson is coming. And when he arrives, he won’t just be a prospect getting a cup of coffee. He’ll be a player who’s ready to contribute-and ready to win.