Filling the role of spot starter, Mitre was hit hard by the Royals on Saturday at Yankee Stadium, allowing seven runs (five earned) in 4 1/3 innings, his first appearance since returning from the disabled list and a strained left oblique.
"We tried to prepare Serge to start, and I just didn't see the crispness necessarily in his pitches," Yankees manager Joe Girardi said. "I don't think he's physically ready. He probably could have used some more time, so we're going to try to get him right in the bullpen."
Moseley steps into the role vacated by an injury to left-hander Andy Pettitte, and Girardi believes the 28-year-old right-hander should be more built up in terms of stamina.
Moseley has a 4.22 ERA in four relief appearances for New York, spanning 10 2/3 innings, but he has also made 12 starts at Triple-A Scranton/Wilkes-Barre. Meanwhile, Mitre will be available to the Yankees in a role as a long reliever beginning Wednesday.
"I think he's disappointed, which I would expect," Girardi said. "[Starting is] what he wants to do, and I understand that."