Sean Marshall (3-4) made one mistake, and that was to Ausmus. The left-hander gave up four hits and three walks over seven innings. Marshall struck out five and now has 47 Ks for the season, which ranks among the National League rookie leaders.

Marshall was making his 12th start, which is tied for the most in the Major Leagues this season by a rookie with Pittsburgh's Paul Malholm.

The Astros took the series, 2-1, in front of a sellout crowd of 42,492 at Minute Maid Park.

Sampson (1-0), filling in for injured Roy Oswalt, made the most of his first start. The right-hander did not allow a hit over 4 1/3 innings before John Mabry hit a comebacker that Sampson booted into foul territory. Mabry was credited with a hit. For the game, Sampson gave up three hits and one walk over seven innings.

Ausmus gave the Astros a 1-0 lead with his first home run off a 1-0 pitch from Marshall leading off the third.

Jason Lane thought he'd given Houston a 2-0 lead with a leadoff homer in the fifth, but the umpires conferred and ruled it was foul. Turns out Ausmus' hit was all the Astros needed.

This story was not subject to the approval of Major League Baseball or its clubs.