Bryan Woo Returns to Mariners Rotation After Shoulder Discomfort

Bryan Woo is expected to rejoin the Seattle Mariners’ starting rotation for the series finale against the Philadelphia Phillies after recovering from right shoulder discomfort sustained during his August 16 start in Houston, according to Mariners general manager Justin Hollander.

Woo reported feeling "100% confident" in his readiness following a bullpen session on August 23, which indicated he avoided a stint on the injured list. The Mariners are now considering a six-man rotation as they manage pitching workloads late in the season.

Hollander said the Mariners have yet to finalize plans for the rotation and will evaluate based on performance and how pitchers handle rest. He commented, "We haven't made any decisions as of today. I don't anticipate a six-man rotation as like a new thing the Mariners are going to do for the rest of ’26 and ’27 and ’28, and we're just going to be a six-man rotation team. We'll evaluate the situation as we go."

Woo’s shoulder discomfort caused him to exit his August 16 outing early after 75 pitches. Since then, he has not been able to reproduce the soreness and reported feeling great during bullpen work, according to Hollander.

"He had never felt anything like that before," Hollander said. "He has not been able to reproduce it since then. It felt a little sore in the couple days afterward; felt nothing out there [on Sunday].

He felt great. So he feels ready to go."

In addition to Woo, the Mariners have been managing extra rest for pitchers George Kirby and Bryce Miller due to lat discomfort and other fatigue-related issues. Miller has struggled with a 7.19 ERA over his past eight starts, contributing to Seattle’s recent losses.

Hollander noted that Miller is not currently concerned about his condition and has not been on the injury report since August 2. "Bryce is not making excuses at all, and I don't think he wanted it to come off that way," Hollander said.

The Mariners are mindful of the bullpen strain caused by a six-man rotation since carrying six starters reduces bullpen depth under current roster limits. However, September roster expansions may alleviate this by allowing additional pitchers.

"There’s just different challenges," Hollander explained. "It’s not as much of a challenge if you have six starters and they’re all pitching six innings at the top. When you have six starters and getting much shorter outings than that, it’s a huge challenge. But we will figure out a way to do the right thing for the Mariners and the right thing rest-wise for the starters."

Woo’s home performance has been notably stronger than on the road this season. At T-Mobile Park, he holds a 1.96 ERA in 10 starts, compared to a 5.96 ERA in 14 road starts. He faces a Phillies lineup that has scored only three runs in the first two games of the series, presenting an opportunity for a strong outing.

Despite a 9-8 record and 4.10 ERA, Woo’s underlying metrics remain promising. His 3.29 FIP and 1.08 WHIP indicate solid pitching performance, with 137 strikeouts and only 29 walks in 138 1/3 innings, demonstrating his ability to miss bats and limit free passes.

Woo acknowledged the challenge of balancing rest with team needs during this critical late-season stretch. "It’s just being smart about what’s realistic. Being smart about a couple of days off and coming back and not missing much time," he said.

"It’s a really tough balance, especially this time of year, especially with the position that we’re in. We don’t have any room for grace. It’s a sprint now."

He added that understanding his own body helps him manage recovery. "I think it’s all understanding your own body and yourself and how you know everything is supposed to feel and how everything’s supposed to move. So it wasn’t one of those things where I felt like, you know, the season was in jeopardy or something like that.

It was just a matter of what’s the proper way of going about this. I’m dealing with it the right way, but I’m also staying on the field."