Seattle Mariners shut down George Kirby with arm trouble

Mar 7, 2025, 12:48 PM | Updated: 1:18 pm

Editor, Seattle Sports

The Seattle Mariners have been able to avoid serious injury in recent seasons to any of their five standout starting pitchers, and they’re hoping to keep it that way. But right now, they’ve got a problem to monitor.

Right-hander George Kirby has been scratched from a scheduled Cactus League start Friday night and is being shut down for a short period with shoulder inflammation.

Mariners insider Shannon Drayer of Seattle Sports has the report from the team’s spring training camp in Peoria, Ariz., adding that no structural damage was found in an MRI of Kirby’s shoulder.

Mariners general manager Justin Hollander delivered the news to reporters in Peoria on Wednesday afternoon.

#Mariners General Manager Justin Hollander shares an injury update on George Kirby. https://t.co/Evwi5GBVh0 pic.twitter.com/lAPmZOU42u

— Seattle Sports (@SeattleSports) March 7, 2025

“He just hasn’t felt like he’s bouncing back great (after outings in spring training),” Hollander said of Kirby. “We did an MRI, MRI looks great, no structural concerns. There is some inflammation in there that we need to get out, so much to George’s chagrin, we’re going to take the ball out of his hands.

“George wants to keep going and he’s going to lose this argument. We need the inflammation out so we will shut George down and work on getting the inflammation out.”

Hollander called it a “week-to-week thing” and said he expects Kirby will start the regular season on the injured list after not having a full spring training of building up his arm.

“He was pretty adamant that this was fine, but again, it’s March, it’s not October,” Hollander said. “We need George for seven months this year if you’re counting all of October, and so the right thing to do is to take it out of his hands and make sure that he is feeling great when he’s out there.”

What now for the Mariners’ rotation?

The Mariners are set to host the Los Angeles Dodgers at 5:40 p.m. Friday at the Peoria Sports Complex. Radio coverage will be carried on Seattle Sports 710 AM, SeattleSports.com and the Seattle Sports app beginning at 5:30 p.m.

Emerson Hancock has slid in as Kirby’s replacement to start Friday, and he is the most likely choice to move into the Mariners’ rotation to start the season in place of Kirby.

Emerson Hancock to start tonight. No timeline for Kirby, the shoulder will determine when he throws again. Have to get the inflammation out.

— Shannon Drayer (@shannondrayer) March 7, 2025

Hancock, 25, was Seattle’s first-round draft selection in 2020. He spent most of the 2024 season with Triple-A Tacoma but made 12 starts for the M’s, most of which came at the start of the year while Bryan Woo recovered from an arm issue. Hancock went 4-4 with a 4.75 ERA and 1.335 WHIP last year in the big leagues.

The 27-year-old Kirby finished his third MLB season last year, going 14-11 with a 3.53 ERA, 1.068 WHIP and 191 innings. He led MLB in walks per nine innings (1.084) and strikeouts to walks ratio (7.783), tied for the MLB lead with 33 starts, and was ninth in innings pitched (191).

Why Mariners’ Mitch Garver as catcher clicked with George Kirby

The No. 20 overall pick in the first round of the 2019 MLB Draft by Seattle, Kirby has a rare ability to throw a high rate of strikes while being able to reach 100 mph with his fastball. He debuted with the Mariners in 2022, helping the team reach the postseason for the first time in 21 years and even registering a save to lock up an American League Wild Card Series win over the Blue Jays in Toronto.

Kirby was an AL All-Star in 2023, going 13-10 with a 3.35 ERA and 1.038 WHIP. He also led MLB that year with 0.9 walks per nine innings and 9.05 strikeouts per walk.