Wainwright strained the muscle on Monday while putting a 45-pound weight back on a rack. General manager John Mozeliak said Thursday the strain is about belt high.
Wainwright said the pain originally felt like a twinge when it first occurred and the injury bothered him when he ran or lunged but did not affect his pitching. He walked off a practice field Tuesday following the team's stretch, returned to St. Louis on Wednesday and was examined by Dr. Michael Brunt on Thursday.
