It was a very believable story, it just seems a little too convenient to me that the one time he accidentally uses a corked bat, it happens to explode all over the infield. I don't really care because the advantage it gave him was pretty small, and Sammy didn't hit many bucket homeruns anyway. It does show that he's willing to cheat to get an advantage, which when added to the rest of the circumstantial evidence makes me believe 100% that he did steroids.