http://espn.go.com/mlb/spring2012/story ... -4-6-weeks
Chris Perez couldn't even finish his first bullpen session without trouble.
Now he has to save Opening Day.
Cleveland's All-Star closer will miss at least one month and possibly six weeks with a strained left side muscle he injured throwing off the mound for the first time in spring training. Perez said Sunday he had thrown about 30 pitches Thursday when he pulled up with what he thought was a cramp.
Instead, he strained an oblique muscle.
"Just one of those fluke things," he said.