Oswalt leaves start early with hamstring strain

KISSIMMEE, Fla. (AP) - Astros ace Roy Oswalt left his start against the Pittsburgh Pirates after four innings because of a hamstring strain.

General Manager Ed Wade said Friday that Oswalt first experienced pain on the same side Sunday after his start against the Mets was rained out and he pitched in the bullpen. Oswalt felt a pinch or tug on his rear end a few pitches into his session.

Oswalt gave up one run on three hits over four innings and struck out six against the Pirates before his early exit. He threw 60 pitches.

Friday was just his third outing of the spring. He had recorded just six innings thanks to a pair of rainouts.

Wade said Oswalt would travel back to Houston tonight or Saturday to be evaluated by the team doctor.

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