Mariners' best young hurler recently got promoted (and it's not the switch-pitcher)

The Seattle Mariners continue to showcase their strong track record of developing young pitching talent, and the latest example is the promotion of Ryan Sloan to High-A Everett.

At just 19 years old, Sloan is proving to be one of the most polished young arms in the organization, demonstrating a maturity on the mound well beyond his age. In his first full professional season, he is solidifying himself not only as one of Seattle’s most important prospects, but as a rising name across all of baseball.

Sloan entered the system with plenty of promise, but few could have predicted how quickly he would establish himself as a cornerstone piece of the Mariners’ farm system. He is already ranked as the team’s No. 2 pitching prospect, behind only 2025 first-rounder and third overall pick Kade Anderson and well ahead of famed switch-pitcher Jurrangelo Cijntje.

Ryan Sloan's stock is soaring in Mariners farm system

MLB Pipeline catapulted him all the way up to No. 42 in their most recent top 100 rankings, a testament to how impressive his development has been since turning pro. For an organization that prides itself on building around homegrown pitching, Sloan’s trajectory is yet another reason for excitement.

In his Everett debut on Saturday, Sloan showcased exactly why scouts and evaluators are so high on him. Across four innings, he allowed just one earned run on four hits, striking out two while issuing no walks. He now has a 1.66 ERA to show for his last nine outings overall, with 36 strikeouts against just six walks.

While Sloan's first High-A stat line doesn’t scream dominance, it highlights his poise and command. For a teenager facing more advanced competition, his ability to stay composed, attack hitters, and avoid free passes is a clear marker of his advanced skill set.

What makes Sloan particularly intriguing is not just his polish, but his projection. His fastball already plays well against older hitters — he is 4.2 years younger than the average player at High-A — and his secondary pitches show the kind of refinement that often takes years to develop. Add in his calm demeanor on the mound, and it’s easy to see why some scouts believe he has the makings of a future front-of-the-rotation starter.

Sloan’s promotion is both a reward for his performance and a signal that the Mariners view him as a fast riser in their system, despite being a teenaged right-hander they drafted out of high school just last year.

While he’s still likely a few years away from T-Mobile Park, he may arrive sooner than most originally thought. If his development continues at this pace, Sloan could become one of the next great arms in Seattle’s wave of pitching talent.