The Seattle Mariners are making room for Kade Anderson, and the ripple effect is already hitting the rotation.
Anderson, the left-hander ranked No. 5 on MLB Pipeline’s top 100, is set to make his major league debut in the second game of Seattle’s three-game series against the Chicago Cubs on Saturday at 4:15 p.m. PT at T-Mobile Park. For a team that has been waiting on one of its premier pitching prospects, the moment finally arrives this weekend.
That debut pushed Bryan Woo out of the planned Saturday start. Woo had been lined up for the Cubs series, but after dealing with shoulder discomfort in his last outing against the Houston Astros on Aug. 16, he’ll get a few extra days to recover and will not pitch in the series against Chicago.
Mariners manager Dan Wilson said Woo is not expected to hit the injured list and has not had imaging on the shoulder.
"He was scheduled to go tomorrow but will likely get slotted in here at some point," Mariners manager Dan Wilson said in a pregame interview Friday. " ... We don't anticipate an IL (stint)."
Woo’s last start still ended as a quality outing despite the shoulder issue. Against Houston, he struck out five, walked one, hit a batter and gave up two earned runs on three hits, including two homers, over six innings. It was also the 2025 All-Star’s first quality start on the road since May 12, which came against the Astros as well.
Through 24 starts, Woo has a 4.10 ERA with 137 strikeouts in 138.1 innings.
Bryce Miller will take the ball in the series finale against the Cubs on Sunday, and Seattle will then reset the rotation for the second half of its six-game homestand, a three-game set against the Philadelphia Phillies that begins at 6:40 p.m. PT on Sunday.
Wilson wasn’t ready Friday to say whether Anderson’s promotion is temporary or whether it will send the Mariners back to a six-man rotation or a piggyback setup, which the club used earlier this season.
"I think we continue to talk about that and see what will make the most sense for us going forward," Wilson said. "And I think once we get Bryan slotted in, we'll figure out exactly how we'll proceed. ... (Anderson's) here to start for us tomorrow and I think, going forward, I'd imagine it's similar."
Still, the direction appears to be coming into focus. A report from Seattle Times writer Adam Jude, published two hours after Wilson’s pregame comments, said the Mariners are planning to return to a six-man rotation for now, with Woo, Miller, Anderson, Emerson Hancock, George Kirby and Logan Gilbert in the mix, according to a source.
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