The Seattle Mariners are expected to officially open up a 40-man roster spot by non-tendering hard-throwing reliever Gregory Santos on Friday afternoon, per reporting from Francys Romero, who posted the following on social media just ahead of the official deadline:

The Seattle Mariners have non-tendered right-hander Gregory Santos, per sources.

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The 26-year-old Dominican right-hander will become a free agent. He pitched 7 innings in MLB with the Seattle Mariners during the 2025 season.

Acquired from the Chicago White Sox before the 2024 season, Santos was supposed to pair with Matt Brash and Andres Munoz to form a great back-end bullpen trio, but it just never materialized.

Brash missed all of 2024 with Tommy John surgery and Santos made only eight appearances, pitching to a 4.91 ERA.

It wasn’t much better in 2025, as he also only made eight appearances, pitching to a worse 5.14 ERA. He struck out just six hitters in 14.1 career Seattle innings, and he walked 10 (two intentional).

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Given that Santos was only projected to make $800,000 next season, and that he’s only 26 years old, this is a surprising decision. Evidently, the Mariners feel good enough about their collection of arms that they don’t want to even give Santos a chance to compete for a spot in spring training.

Brash, Munoz, Gabe Speier, Eduard Bazardo and Carlos Vargas seem like locks for the bullpen, while Robinson Ortiz, Casey Legumina, Blas Castano, Logan Evans, Emerson Hancock, Alex Hoppe, Jackson Kowar, Ryan Loutos, Trent Thornton and Cole Wilcox are current candidates for ‘pen spots.

Of course, Seattle could go sign someone else as well to put into the mix.

Seattle Mariners reliever Gregory Santos (48) delivers a pitch during the eighth inning against the Los Angeles Angels at T-Mobile Park. Stephen Brashear-Imagn Images

Seattle Mariners reliever Gregory Santos (48) delivers a pitch during the eighth inning against the Los Angeles Angels at T-Mobile Park. Stephen Brashear-Imagn Images

Santos will head to free agency, where he figures to get another chance because of his fastball and his youth. He could re-sign with Seattle, but that would be on a minor league deal, which likely wouldn’t be appealing to him. Perhaps his old team, the Chicago White Sox, mired in their own rebuild, could give him a call.

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–Gregory Santos for RHP Prelander Berroa (Mariners’ No. 15 prospect), and OF Zach DeLoach (No. 25 prospect), No. 69 overall pick in 2024 Draft.

Berroa is currently out with his Tommy John surgery while DeLoach is currently still at Triple-A for Chicago, proving that in this trade, there were no winners. At least not at the moment.

LATEST PODCAST IS OUT: Brady Farkas is back for the the latest episode of the Refuse to Lose podcast! He covers more on Josh Naylor’s press conference, the latest on Colt Emerson’s Opening Day chances and more. LISTEN HERE: 

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