The Red Sox entered the season with three lefties with sky-high potential in Triple-A Pawtucket, but will likely finish the season with one of them in a doctor's office.
Eduardo Rodriguez and Henry Owens are in the major leagues, but Brian Johnson is still resting his sore arm.
Johnson, who last started for Pawtucket on Aug. 2 and left the mound with elbow tightness, will be reevaluated on Oct. 1, three days before the Red Sox end their season in Cleveland.
"I dont know whether he continues resting and rehabbing, whether he begins a throwing program -- he’s an injured pitcher right now we’re trying to figure out exactly what the best situation is for him," said interim manager Torey Lovullo.