The latest on Mariners starter Bryan Woo’s injury

Seattle Mariners starting pitcher Bryan Woo is day-to-day with pectoral inflammation following his early exit from Friday night’s series opener against the Houston Astros, Seattle Sports M’s insider Shannon Drayer reported on social media.

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Manager Dan Wilson told reporters before Saturday’s contest that results from an MRI showed “minor” inflammation in Woo’s pectoral muscle and that it was “in a lot of ways good news.”

The Mariners are awaiting to see how their standout right-hander’s injury responds to treatment and expect to know more about his status in the next day or two, Drayer reported.

MRI on Bryan Woo reveals inflammation in the pectoral muscle. M’s will take it day-to-day and see how he responds to treatment and go from there. Dan Wilson said they should know more in the next day or two.

— Shannon Drayer (@shannondrayer) September 20, 2025

Woo’s next scheduled start is Thursday in Seattle’s series finale with the Colorado Rockies at T-Mobile Park. However, an off day Monday could give the team a chance to shuffle its rotation if Woo needs extra time off or a stint on the injured list.

Woo was pulled from the opener of Seattle’s pivotal three-game American League West showdown in Houston after making some awkward throws to the mound during his warmup pitches for the bottom of the sixth inning. He was at just 67 pitches.

The right-hander Friday night said he had felt good throughout the game before the pec issue cropped up in the fifth inning. He alerted trainers at the time and said he wasn’t able to get loose while warming up for the sixth.

“I felt great all game, just felt it at the end, and just felt it was smart to not try and push it,” Woo said at the time.

Woo still ended up earning his 15th win of the season with five shutout innings of work in Seattle’s 4-0 victory. He struck out seven with only one hit and one walk allowed. But the early exit kept Woo from recording his 28th outing with at least six innings pitched in 30 starts this season.

The Mariners (85-69) gained sole possession of first place in the AL West and took over the AL’s No. 2 seed for the playoffs with the win.

Woo, a third-year pro, has emerged as the Mariners’ most reliable starter in a talented rotation that was hit by injuries early in the year. He set a franchise record with 25 straight starts of at least six innings to start the season, and set an MLB record with 25 starts with at least six innings pitched and two or fewer walks allowed, which was previously held by Hall of Famer Juan Marichal.

The 25 year old has a 15-7 record, 2.94 ERA and 0.93 WHIP with career highs of 198 strikeouts and 186 2/3 innings pitched. He’s fourth in the AL in innings pitched and fifth among qualified starters in ERA.

The Mariners and Astros continue their three-game series Saturday at 4:10 p.m. Radio coverage begins at 3 p.m. with the pregame show on Seattle Sports 710 AM and the Seattle Sports app.

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