TAMPA, Fla. -- Joba Chamberlain has a strain of the oblique muscle on the left side of his rib cage and will not pitch for an indeterminate length of time.
New York Yankees manager Joe Girardi said an MRI of the area "came back positive" for the strain, and that for now, Chamberlain will be limited to playing catch until the team can determine the seriousness of the injury.
"Any time you hear a strain, that's bad news," Girardi said. "It's not what you want to hear. But right now, he feels good. He's asymptomatic. So he'll play catch tomorrow and we'll go from there. But throwing is different from doing tests in the trainer's room, so we'll see."
Chamberlain had not yet met with Girardi when he arrived in the clubhouse around 1 p.m. ET Wednesday afternoon and was unaware of the club's plans for him.
But he concurred with Girardi that the injury was causing him no pain, and in fact, was not limiting from doing anything other than pitching.
"I sleep good, I roll over fine," he said. "I can cough, I can sneeze, I can stretch. I have no soreness. I have no pain. But I guess we're going to err on the side of caution."
Chamberlain suffered the injury while pitching March 11 against the Braves.
"It was like a cramp, a little spasm kind of thing, and I finished the inning," Chamberlain said. "I mean, I knew it was there but it wasn't something like where I had to stop and catch my breath. I felt it, but I wasn't gonna stop pitching. It was something I really didn't think was that big a deal."
Chamberlain, who came to camp slightly overweight, a condition that was remarked upon by general manager Brian Cashman, has thrown five innings this spring, allowed six hits and two runs for an ERA of 3.60.
After exploding onto the scene as a rookie after being called up in mid-season 2007, he has gradually seen his role diminish from setup man and heir apparent to closer Mariano Rivera, to where he is now, in the middle relief mix, along with David Robertson, Boone Logan and Pedro Feliciano, in trying to get the ball to new setup man Rafael Soriano.
Asked Wednesday if he expects Chamberlain to be ready to break camp with the club on March 29, Girardi said, "I sure hope so. I mean, the fact that he's playing catch tomorrow is a good sign, but doing things in the training room and doing things where there's effort and intensity and torque, it's different."