Seattle Mariners announce ALCS roster with 2 changes

Hours ahead of their ALCS Game 1 matchup against the Blue Jays in Toronto, the Seattle Mariners have announced their roster for the best-of-seven series, electing to go with 13 pitchers and 13 position players.

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As expected, 2025 All-Star starting pitcher Bryan Woo has been added to the roster. Woo, who has been out since exiting a Sept. 19 start against the Astros with pectoral tightness, threw a bullpen Friday in Seattle to determine his readiness. He is not expected to pitch early in the series and is likely to be on a limited pitch count when he does make an appearance.

In addition to Woo, utility man Miles Mastrobuoni has been added to the ALCS roster, with outfielder/first baseman Luke Raley and third baseman Ben Williamson placed on the taxi squad to make room.

Lock it in 🔒 #SeizeTheMoment pic.twitter.com/gXrBeOnket

— Seattle Mariners (@Mariners) October 12, 2025

The Blue Jays have also made changes from their ALDS roster. While the team had hoped to have shortstop Bo Bichette back in some capacity for the ALCS, it was determined he was not ready to go after a workout Saturday at Rogers Centre. Bichette has been on the injured list with a knee sprain since early September.

On the pitching side, the Blue Jays added veteran starters Max Scherzer and Chris Bassitt to their roster.

OFFICIAL: Presenting our ALCS roster! #WANTITALL pic.twitter.com/32YoWSAnBD

— Toronto Blue Jays (@BlueJays) October 12, 2025

Game 1 with Bryce Miller and Kevin Gausman to take the hill is scheduled for 5:03 p.m. Sunday, with the pregame show at 4. Click here for details on how to hear Mariners Radio Network broadcasts from Seattle Sports.

More on the Seattle Mariners

• ALCS Preview: Mariners face Toronto after marathon in ALDS
• Heat Check: Who’s hot, who’s not as M’s enter ALCS
• Seattle Mariners’ ALCS schedule against the Blue Jays
• The crazy numbers behind Mariners’ 15-inning ALDS classic
• ‘Best day ever’ for Seattle Mariners’ unlikely Game 5 hero Leo Rivas

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