HOUSTON - Roy Oswalt threw his second straight shutout and set a Houston record for consecutive scoreless innings, helping the surging Astros beat the Pittsburgh Pirates 6-0 Thursday night for their 14th win in 15 games.

Houston was 66-66 and 11 games back of Milwaukee, the National League wild-card leader, before the surge began Aug. 27. The latest win closed the Astros within three games of the Brewers, who lost at Philadelphia.

It’s uncertain when the Astros will play again. The first two games of their weekend series against the Chicago Cubs were postponed and Sunday’s matchup could be next with Hurricane Ike closing in on Texas.

Oswalt (15-9) hasn’t allowed a run in 32 1/3 innings, passing the previous record of 31 set by J.R. Richard in 1980. He needed only 90 pitches to finish his sixth career shutout and 15th complete game.

Oswalt retired 20 in a row after Luis Rivas’ one-out single in the first inning on his way to winning for the ninth time in 10 decisions. He finished with a three-hitter.

The Astros have won six straight and their 36-16 record since the All-Star break is the best mark in the majors.