Red Sox’ Wyatt Mills (right elbow inflammation) behind in throwing program, Alex Cora says

Injured Red Sox reliever Wyatt Mills is behind in his throwing program, manager Alex Cora told reporters (including MassLive.com’s Christopher Smith) prior to Saturday’s 14-5 win over the Tigers in Detroit.

Mills began the season on the 15-day injured list with right elbow inflammation. The right-hander was initially shut down from throwing shortly after allowing four runs on four hits, one walk, and two hit batsman in one inning against the Blue Jays in his final outing of the spring on March 13.

Prior to that, though, Mills had pitched well in Grapefruit League play, yielding just one run on three hits, four walks, and 10 strikeouts over four appearances spanning five innings of work in which he held opposing hitters to a .158 batting average against.

As MassLive.com’s Chris Cotillo reported last month, Mills was officially diagnosed with elbow inflammation in his right flexor muscle. And while the 28-year-old was able to start playing catch earlier this week, his progress has been slower than anticipated.

“Right now, he’s a little bit behind,” Cora said of Mills at Comerica Park. “He hasn’t started his throwing program yet. Not responding the way we thought in the beginning.”

The Red Sox acquired Mills from the Royals in exchange for relief prospect Jacob Wallace back in December. The Gonzaga product is coming off a 2022 campaign in which he forged a 4.60 ERA — but much more respectable 3.62 FIP — with 26 strikeouts to 13 walks over 27 appearances (29 1/3 innings) between stops in Seattle and Kansas City.

Equipped with a unique sidearm delivery, Boston brought in Mills hoping that he could replicate the same sort of success fellow reliever John Schreiber enjoyed during his breakout season last year. Like Schreiber, the 6-foot-4, 214-pound Mills  throws from a similar angle and operates with a three-pitch mix that consists of a four-seam fastball, a slider, and a sinker.

Given Saturday’s development, when Mills will be cleared to start pitching in games again is an unknown at this point. Looking ahead, Mills — who does not turn 29 until January — has just one minor-league option remaining but is not eligible for salary arbitration until 2026.