Athletics' Kazmir leaves early with left shoulder tightness, will undergo MRI

Oakland Athletics starting pitcher Scott Kazmir left Wednesday's clash with the Detroit Tigers in the fourth inning with left shoulder tightness.

Kazmir tossed three scoreless innings before pointing to his throwing shoulder in the dugout, indicating the injury. He underwent an MRI following the contest, and manager Bob Melvin isn't sure if his hurler will require a stint on the disabled list.

"He probably felt he could continue to pitch," Melvin told reporters after the game, "but it didn't make any sense to. I think it just started bothering him as the game went along. You could tell he was a little bit uncomfortable after the last pitch when he was coming off the mound. His body language wasn't great, so we didn't want to push him."

Kazmir, who is making $13 million and will be a free agent at season's end, figures to be an important trade chip for general manager Billy Beane down the stretch. A long-term injury could throw a serious wrench in Beane's ability to deal the southpaw to a contender and restock his minor league system.

The left-hander also has an extensive history of shoulder problems, which includes a stint on the disabled list in 2010 due to fatigue.

Kazmir entered play Wednesday with a 2-3 record, 3.09 ERA, and 1.25 WHIP in nine starts.