Moyer, who underwent surgery Oct. 2 to repair three torn muscles in his groin and lower abdomen and was to miss the rest of the season and postseason, was "doing fine" and has been in Thomas Jefferson University hospital in Philadelphia since Wednesday, Amaro said.
Moyer has "some type of blood infection and will likely stay one more night, getting the fever down and taking antibiotics," Amaro said, according to The Philadelphia Inquirer. "Not sure how he got it."
Moyer's wife, Karen, confirmed in an e-mail to The Associated Press on Saturday that her 46-year-old husband was doing OK.
Moyer, who went 12-10 with a 4.94 ERA in 30 games this season, including 25 starts, sustained the groin and abdomen injuries late last month while throwing a pitch during a relief outing against the Houston Astros.