Seattle Mariners pitcher Gregory Santos (right) talks with catcher Cal Raleigh during a game against the Texas Rangers on April 12 at T-Mobile Park. Joe Nicholson-Imagn Images

Seattle Mariners Sent Strong-Armed Reliever Gregory Santos to Triple-A

Originally posted on Seattle Mariners on SI
By Teren Kowatsch | Last updated Apr 16, 2025 6:30 PM ET

The Seattle Mariners bullpen has been one of the most volatile units on the team in 2025 in terms of transactions. Right-handed relievers Troy Taylor and Matt Brash began the year on the 15-day injured lists with respective injuries. Taylor was just activated off the injured list on Monday.

The Mariners have one of the highest-ranking bullpens in the league in terms of innings pitched. And that's forced them to go to make several roster moves and transactions to cover the relievers' high usage.

Seattle's latest move related to the bullpen will temporarily demote one of the strongest arms on the team to the Triple-A Tacoma Rainiers.

Before Game 2 of a three-game series against the Cincinnati Reds on Wednesday, the Mariners optioned right-handed pitcher Gregory Santos to Tacoma. They recalled right-handed reliever Will Klein in a corresponding move.

Roster moves:

Will Klein, RHP, recalled from Triple-A Tacoma.
Gregory Santos, RHP, optioned to Triple-A Tacoma.

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— Mariners PR (@MarinersPR) April 16, 2025

Santos has had a chaotic stint with Seattle. The organization acquired him in a trade with the Chicago White Sox on Feb. 3, 2024. He was out for most of last season due to two separate stints on the injured list: one for a right lat strain and the other for right biceps inflammation. Santos pitched in eight games last season and had a 4.91 ERA with six strikeouts in 7.1 innings pitched.

This season, Santos has had eight outings already. He has a 5.14 ERA in seven innings pitched and is yet to record a strikeout. He's allowed six runs (four earned) in his last four appearances.

Santos has one of the strongest arms on the pitching staff with a fastball capable of hitting triple-digits. But he's struggled with command to start the year.

The Mariners will hope Santos can recover his form with the Rainiers that he had with the White Sox. In 2023, Santos had a 3.39 ERA in 60 appearances with 66 strikeouts in 66.1 innings pitched.

This article first appeared on Seattle Mariners on SI and was syndicated with permission.

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