Bleier walked off the mound in pain Wednesday after throwing a seventh-inning pitch against Boston. An MRI determined the injury to be a left shoulder latissimus strain, which probably will require surgery to repair.
"I don't expect him to play again this year," manager Buck Showalter said Friday. "The worst case is that it's a Grade 3 [strain] and he has surgery and returns sometime next season."
Bleier, whose 31 appearances are most on the staff, was placed on the 10-day disabled list.
"It's a loss," Showalter said. "It's very valuable to have a left-handed pitcher who can pitch to both sides. He keeps you from having to [warm up] behind him because you know you can leave him in there for an extended period of time."
The Orioles made a flurry of moves Friday, recalling left-handed reliever Tanner Scott from Triple-A Norfolk, selecting the contract of infielder Corban Joseph from Double-A Bowie, optioning right-hander Yefry Ramirez to Norfolk and designating lefty D.J. Snelten for assignment.
Joseph started at first base Friday night against Miami in place of Chris Davis, who has essentially been benched in the wake of a season-long slump.
Davis is batting .150 with four home runs, 15 RBIs and 86 strikeouts in 52 games. Making matters worse is that the slugger is in the third year of a seven-year, $161 million contract.
Davis hasn't played since Monday, and there's no telling when he will be back in the lineup.
"Chris is continuing with some things that he's working on," Showalter said. "When they come to me and say they think he's ready to get back in the lineup, we'll put him back in there. But it's nothing imminent."
Asked to disclose whom Davis is working with, Showalter said, "I'm not going to get into all that. When they think that he's ready to play, he'll play. I hope it's tomorrow. I hope it's the day after tomorrow. It's not today, and there's no closed end on it. I'm hoping it's sooner rather than later."