The Boston Red Sox are moving right-hander Walker Buehler to the bullpen, manager Alex Cora told reporters on Friday, hours before first pitch against the New York Yankees (GameTracker). 

The Red Sox elected not to announce who will take Buehler's spot in their starting rotation. His turn to start is due up next on Monday, meaning they'll have a few days to decide for certain. Left-hander Kyle Harrison, obtained in the Rafael Devers trade, would be available on five days' rest and would be making his Boston debut if he is indeed the choice. 

Buehler, 31, joined Boston on a one-year pact worth $21 million with a mutual option for the 2026 campaign. In 22 starts to date, he amassed a 5.40 ERA (76 ERA+) and a 1.52 strikeout-to-walk ratio. His performance was considered to be below replacement, according to Baseball Reference's calculations -- that despite a recent run that saw him post a 3.77 ERA in his past eight starts. (To be fair, he did so while recording nearly as many walks as strikeouts.)

Buehler made several tweaks to his game throughout the season, including dropping his arm angle and altering his pitch mix, but nothing allowed him to return to his past form, when he was a legitimate candidate to win the Cy Young Award.

Indeed, Buehler was one of the top starters in baseball when his body permitted him to perform between the 2017-22 seasons. In 115 appearances (106 of them starts), he compiled a 136 ERA+ and 4.26 strikeouts for every walk. He notched 13.5 Wins Above Replacement. 

The Red Sox entered Friday with a 69-59 record, putting them a half game behind the Yankees for the top wild card spot. Additionally, the Red Sox are five games back in the AL East.