Cubs pitcher Matthew Boyd injures his left knee while sitting down with his kids at home

CHICAGO (AP) - Chicago Cubs pitcher Matthew Boyd is going to have surgery after he injured his left knee while hanging out with his kids on Wednesday.

Boyd had an MRI that showed a meniscus issue, and manager Craig Counsell said the team isn't sure how long the left-hander is going to be out.

"Obviously it's unexpected news," Counsell said. "We're going to have to fill in around him, for sure. That's going to be our task."

Boyd was placed on the 15-day injured list before Chicago's game against the Cincinnati Reds. Right-hander Trent Thornton was brought up from Triple-A Iowa, and left-hander Charlie Barnes was designated for assignment.

The 35-year-old Boyd, who started for the Cubs on opening day, is 2-1 with a 6.00 ERA. He was activated from the 15-day IL on April 22 after being sidelined by a biceps strain.

Counsell said Boyd got hurt when he sat down with his kids and got back up.

"It happened very innocently, and he woke up this morning a healthy player. ... So he's just trying to kind of process it," Counsell said, "and get all the information from the doctors and figure out what's next."

The loss of Boyd is a major blow for NL Central-leading Chicago, which had won seven in a row and 17 of 20 overall going into the matchup with Cincinnati.

The Cubs were already playing without right-hander Cade Horton, who is out for the season because of elbow surgery. Justin Steele is expected to return at some point this year, but his timeline is cloudy after he had a setback in his recovery from an elbow injury.

Boyd agreed to a $29 million, two-year contract with Chicago in December 2024. He went 14-8 with a 3.21 ERA in 31 starts last year, making the NL All-Star team and helping the Cubs reach the playoffs for the first time since 2020.

With Boyd out, Javier Assad could move into the rotation at some point. But Counsell said he wasn't sure how the Cubs would cover Boyd's next scheduled start.

"That spot comes up Friday," Counsell said. "We're probably not going to make plans for it and just kind of figure out where, when we get to, after Thursday, kind of what we do. I mean, there will be plans, but very loose plans."

The Cubs could get some help for their bullpen this month. Relievers Caleb Thielbar and Hunter Harvey are both expected to throw a full bullpen session on Friday, Counsell said. Thielbar is on the IL with a left hamstring strain, and Harvey is coming back from right triceps inflammation.