BOSTON -- Red Sox reliever Joel Hanrahan said Saturday he will undergo season-ending surgery to repair a torn flexor tendon in his right arm and will be out six to nine months.

All indications were that Hanrahan would have surgery instead of a lengthy and uncertain rehab after discussing matters with team doctors, but the need for a procedure became more obvious after he visited noted orthopedist Dr. James Andrews on Friday.

"Initially I thought there might be a decision to make [between rehab and surgery] but after talking to [Andrews] he took one look at my arm, touched it, said there really wasn't a decision," Hanrahan said Saturday morning. "The flexor pretty much tore off the bone. There wasn't really a decision, it was just a matter of what kind of surgery it was going to be. As for now it's just the flexor. When he gets in there and takes a look, could be worse, could be better. That's kind of where we're at now."

Red Sox manager John Farrell said Friday that the ulnar collateral ligament in Hanrahan's elbow is not connected to the injury. Therefore, Tommy John surgery is not known to be necessary at this time. However, the full extent of the damage will not be known until Hanrahan is examined more by Andrews, at which point any ligament issues will be addressed.

Hanrahan said the surgery will be next week, in all likelihood. He is hopeful, if no further damage is discovered in the arm, that his rehabilitation would take closer to six months than nine, and he said he fully expects his career to rebound.