The Boston Red Sox are moving one of their key free agent signings, former All-Star right-hander Walker Buehler, from the rotation to the bullpen.

MassLive had reported that the Red Sox were weighing what to do with the struggling pitcher, and manager Alex Cora confirmed the decision Friday before Boston played the second of a four-game set against the host New York Yankees.

"We'll figure out how he goes. Maybe one inning, multiple innings, whatever it is, we don't know yet," Cora said.

Buehler won't be available Friday as he made his last start Tuesday against the Baltimore Orioles. He used 75 pitches to get through four innings of a no-decision as Boston eventually lost to the O's in extra innings.

An All-Star in 2019 and 2021 with the Los Angeles Dodgers, Buehler signed a one-year deal last offseason with the Red Sox that was worth a guaranteed $21.05 million plus incentives.

He's gone 7-7 with a 5.40 ERA over 22 starts, striking out 82 batters but walking a career-high 54 and allowing a career-worst 21 homers. After a 4-1 start to the season followed by about a month on the injured list (shoulder inflammation), Buehler hasn't been nearly as effective.

Cora said he didn't know who would take Buehler's next scheduled start Monday in Baltimore, and that Buehler accepted the news like a professional.

"I still believe in him," Cora said. "He's a big part of what we're trying to accomplish."