(AP) -- Paul Maholm shut down the Astros for eight innings, Freddy Sanchez homered for the second straight game and the Pittsburgh Pirates beat Houston 8-2 on Tuesday night.

Ryan Doumit hit a three-run homer and Nate McLouth added a solo shot as the Pirates beat the Astros for the sixth time in eight meetings.

Maholm (7-6) allowed a run on five hits, all singles, and struck out five to win for the fifth time in six decisions. He improved to 2-5 on the road this season.

Sanchez, who had a three-run, inside-the-park homer in Monday's 9-3 win, went 3-for-5 with two more RBIs. The Pirates have scored 17 runs in two games against the Astros after scoring only 16 in their previous five, all losses.

Maholm was perfect through 3 1/3 innings until Michael Bourn singled in the fourth.

The 25-year-old left-hander retired seven in a row before Lance Berkman led off the Houston seventh with a single. Berkman scored the Astros' first run on Hunter Pence's two-out single.

Sean Burnett gave up Ty Wigginton's RBI single in relief of Maholm in the ninth.

Sanchez hit a solo shot in the first inning off Houston starter Jack Cassel (1-1), though Sanchez wasn't sure if it was a home run at first.

The ball hit high off the wall in left-center and Sanchez stopped at second. But after Pittsburgh manager John Russell protested, the umpires conferred and ruled the ball hit above the yellow line running along the fans' balcony for a home run.

Xavier Nady led off the second with a double to left, extending his hitting streak to 11 games. After Adam LaRoche singled, Nady scored when Jose Bautista rolled into a double play.

With one out in the third, McLouth drove an 0-2 pitch from Cassel into the restaurant area in center to make it 3-0. McLouth has 18 of his 20 homers this season against right-handed pitchers.

Jack Wilson led off the fifth with a double to left-center and scored on Sanchez's single to left. Sanchez later scored on Jason Bay's single to make it 5-0 and Houston manager Cecil Cooper brought in Chad Paronto to relieve.

The Pirates added three in the seventh when Wilson walked and Sanchez doubled before Doumit drove the first pitch he saw onto the railroad tracks in left field, his 12th homer of the season and fourth hitting right-handed.

The Pirates are 17-7 against the Astros since the start of last season.