Oswalt (7-8) allowed a run and six hits, but walked off the field with a trainer after throwing his warmup pitches for the seventh.
Manager Cecil Cooper said Oswalt strained his left hip abductor in the sixth inning. Oswalt had grounded out in the bottom of the inning and Cooper didn't know if he hurt his hip pitching or hitting.
Cooper said Oswalt was “day-to-day.” The Astros' ace is due to start again in Atlanta on Saturday.
“We'll have to wait and see how he is,” Cooper said. “Right now, I'll say he's fine and he'll take his next start. We'll just have to wait and see.”
Lance Berkman homered and Brad Ausmus added a two-run single off Eric Stults (2-1) to help the Astros win for the seventh time in 10 games. Jose Valverde pitched a scoreless ninth to earn his 22nd save.
James Loney’s sacrifice fly in the first inning drove in the Dodgers’ only run. Los Angeles has scored two runs in their last three games and one run or fewer in five of its last seven games. The Dodgers were no-hit by the Los Angeles Angels on Saturday and managed to win 1-0.
Oswalt had lost four of his last six starts but looked like his dominant self after a shaky first. He gave up a one-out double to Andre Ethier and plunked Russell Martin and Jeff Kent with pitches before Loney’s sacrifice fly scored Ethier.
Berkman hit a solo homer to left in the bottom of the first, his 22nd of the season and his fifth batting right-handed. It was the first homer allowed by Stults in three starts this season.
Oswalt retired the next seven batters he faced before Kent led off the fourth with a single. Miguel Tejada made a sharp back-handed stop on Loney’s grounder to start a double play and Oswalt struck out Delwyn Young to end the inning.
Stults set down eight in a row before walking Berkman with one out in the fourth. Carlos Lee then hit a blooper to center that skipped away from Jason Repko in center field. Berkman slid into third and Lee took second on what was ruled a double.
Repko, recalled from Triple-A on Mondaywent 0-for-5 with four strikeouts.
Stults intentionally walked Tejada to load the bases, but Mark Loretta singled to left to put Houston up 2-1. Loretta had the game-winning hit in Sunday’s 3-2 win over Boston and had a three-run homer in Saturday’s 11-10 victory. One out later, Ausmus singled to center for a 4-1 lead.
The Dodgers put two runners aboard in the fifth and sixth, but Oswalt escaped both times. Oswalt grounded out to Dodgers reliever Ramon Troncoso to end the sixth.
The Houston ace initially seemed fine as he got ready to pitch the seventh but lef moments later.
