By now you've likely heard the news that Jesse Crain will not be pitching for Canada in the WBC. Hooray! Less wear and tear on his arm and less potential glory for the Canadian team! Boo hurt adductor muscle!
So how worried should we be? That depends. I really dislike Crain's calling the injury pain "strong, like a strain". Strong pain to an athlete concerns me. But we do have that great medical staff and they did catch this soon enough that it shouldn't be a tremendous setback, if it mounts to be anything close to one at all.
So the adductor is really three muscles, though unless they go in for an MRI we're not going to know which of the three is strained. Combined they all do the same thing. Want to feel them work? Stand up real quick and do the Captain Morgan pose. Alternately, lean back in your chair and spread your legs. Now, whichever position you chose, bring your legs back together. That was your adductor doing the work. I can't imagine pitching with a strained one feeling particularly good.