Seattle Mariners Add An All-Star To Their Roster

George Kirby has been activated and is making his season debut Thursday night for the Seattle Mariners

It's been a long time coming, but the Seattle Mariners are finally getting their All-Star back in the lineup, as George Kirby has been activated and is making his season debut Thursday night.

George Kirby makes his season debut tonight on the bump for the @Mariners 💪 pic.twitter.com/28qV8bGIWL
— MLB (@MLB) May 22, 2025

Kirby has been out all season after coming down with shoulder inflammation during spring training. In three starts on his rehab assignment with AAA Tacoma, Kirby posted an uncharacteristic 7.20 ERA, though with more Kirby-like control of just 1.8 walks per nine.

Kirby, the Mariners' first-round pick in the 2019 MLB Draft (20th overall), was an All-Star in 2023, and has been an ace atop the Seattle rotation for the last three years. He has a career 3.43 ERA with a 1.09 WHIP. He has impeccable control, with a career mark of 8.5 strikeouts per nine vs. only 1.1 BB/9.

Somehow, the Mariners still managed a 28-20 start to the season without him, as their hitting has been unexpectedly strong. Their starting staff has been weakened recently by injuries to Logan Gilbert and Bryce Miller that have landed them on the injured list. It's unknown if those developments helped push up Kirby's return, but we'll have to see how he holds up after his first start Thursday night.

Kirby joins Luis Castillo and Bryan Woo in the rotation, along with rookies Logan Evans and Emerson Hancock.