The Orioles optioned Baker to Triple-A Norfolk following Saturday's game against the Padres.
Baker was initially recalled by the Orioles on Thursday. In his lone outing Saturday against San Diego, the 29-year-old right-hander allowed one run on two hits while striking out one in one inning. The move makes room on the 26-man roster for right-hander Zach Eflin, whom Baltimore acquired from Tampa Bay on Friday.