GOODYEAR, Ariz. — The first big injury of the season struck the Cubs on Thursday morning.

Right-handed pitcher Caleb Kilian was diagnosed with a strain of his teres major in his right shoulder, which will sideline him until around the All-Star break before he returns to pitching in games.

“It’s obviously looser with that big timeframe, but that’s probably what we’re looking at,” manager Craig Counsell said.

The injury is a tough blow to the righty, who had impressed early on in camp. The 26-year-old had a 1.50 ERA with 4 strikeouts in 6 innings, with his fastball nearing triple digits on the radar gun. It was a welcome surprise after a difficult 2023, where he posted a 4.56 ERA at Triple-A and a 16.88 ERA in 5.1 innings in the major leagues. He’s allowed 23 earned runs in 16.2 innings at the major league level.

“I think Caleb was off to a great start,” Counsell said. “When talking to him, he should be very confident of where he was, right? And that should really help him over the next couple of months here and motivate him that he should be really excited about how he was throwing the baseball.

“There was a lot to like, and he certainly got my attention. I know that.”

The injury should test the Cubs pitching depth. Kilian was always a longshot to make the Opening Day roster, but his performances had put him on the radar as either a swingman or spot starter if an injury arose or the Cubs wanted to build in off days for some of their rotation pieces. Now, the Cubs have one less option to turn to.

The Cubs, though, can now place Kilian on the 60-day IL if they please, creating an opening on their 40-man roster for a non-roster invitee. Righty reliever Carl Edwards Jr., catcher Jorge Alfaro, outfielder David Peralta and infielders Dominic Smith and Garrett Cooper are some intriguing options that could stand to benefit from an open 40-man spot.

Other injury updates

Nick Madrigal suffered a mild strain of his right hamstring, Counsell said Thursday. The hope is to progress him over the next week and see where he’s at after that.

“But still, I would say optimistic,” Counsell said.

Madrigal has had a past of hamstring and lower half injuries and that — coupled with where they’re at in Spring Training — is allowing both sides to play it slow.

“I think today it’s important to remember, it’s March 7 and that’s what I told Nick. It’s March 7, Nick and you do have a history here, so let’s be smart because it’s March 7,” Counsell said. “In season, I think you’re aware of it, but I don’t want to put any limitations on him because of it right now.”

Ian Happ (left hamstring strain) and Patrick Wisdom (right quad) could return to game action this weekend, Counsell said.

Bellinger’s impressive AB

Cody Bellinger worked a walk in Wednesday’s win over the Angels, coaxing an 11-pitch plate appearance that left an impression on his new manager.

“I was like, ‘That’s the dream at-bat [in] your first Spring Training game where you see [11] pitches,” Counsell said. That was what was so impressive to me like that was the right foul balls. That’s kind of what got me excited.

“It’s one of those at-bats — you want that at-bat in Spring Training to get it the first day, it’s like a hat tip to a really good hitter.”

Next Up

The Cubs will play a split-squad game Friday. Shota Imanaga will make his second start of the spring as the Cubs host the Mariners at Sloan Park at 2:05 p.m. Kyle Hendricks will start the second game against the Diamondbacks at Salt River Fields at Talking Stick.