A's reliever Evan Scribner exited Monday's game against the Angels in the ninth inning with an injury and on Wednesday, the severity was revealed.
Manager Bob Melvin told reporters prior to the series finale against the Angels that Scribner has a torn lat muscle and will miss the rest of the 2015 season.
"Scribner has a tear in his lat, so he's done for the year," said Melvin. "Similar to what he had, I guess, a few years back in San Diego."
In his fourth year with the A's, Scribner was in the midst of a rough season. In 60 innings over 54 appearances, he had compiled a 4.35 ERA and allowed 14 home runs, the most among all relievers in the major leagues this season.
But Melvin expects the 30-year-old Scribner, who is under team control for four more seasons, to be back for the 2016 season.
"Prognosis going into spring training is good, but he's done for the year," said Melvin.