SAN DIEGO -- Andy Pettitte is unbeaten in San Diego, and he holds a slim edge over Jake Peavy in their head-to-head matchups.
Pettitte outpitched Peavy in his first game in San Diego since the 1998 World Series, and Morgan Ensberg returned from the disabled list to help spark the Astros to a 1-0 win over the Padres on Tuesday night.
Pettitte and Peavy are both in the odd position of being marquee pitchers with uncharacteristically poor records.
"I kind of know what he's going through a little bit this year, with the year I've had so far," Pettitte said. "That's a tough one to lose. We're both trying to get it going and get on a real good run, and I'm just thankful I was able to throw a good game for us."
Pettitte (10-11) was impressive in his first start in San Diego since winning Game 4 of the 1998 World Series at Qualcomm Stadium, which completed the New York Yankees' sweep of the Padres.
Pitching for the first time at Petco Park, he held San Diego to five hits in six innings, struck out eight and escaped two jams. Pettitte walked two and got the only run he needed on Adam Everett's sacrifice fly in the fourth.
Chad Qualls and Dan Wheeler each worked a hitless inning in relief. Brad Lidge fanned three in the ninth for his 24th save in 28 opportunities.
Astros pitchers struck out 13 in a five-hitter, Houston's NL-best 10th shutout.
"I felt like I was throwing the ball pretty good, but I still felt like I had several jams," Pettitte said. "Obviously, when it's 1-0 it puts a little more heat on you. I felt real good about the way I was throwing the ball and I just didn't want to change anything."
Pettitte and Peavy faced each other for the third time since 2004, and the Houston lefty now has a 2-1 advantage over the Padres' righty.
Peavy (5-11) pitched well, but lost for the sixth time in seven decisions. He was coming off a 10-3 victory against the Los Angeles Dodgers, his only win since May 28. Peavy allowed one run and six hits in seven innings, struck out three and walked one.
"I didn't expect Andy Pettitte to give up three or four runs," Peavy said.
Ensberg, out since July 13 with a bruised right shoulder, was activated before the game and went 2-for-4. He doubled leading off the fourth, advanced on Luke Scott's groundout and scored on Everett's sacrifice fly.
The Padres thought Ensberg should have been out after he checked his swing before the double.
"I hate to get on umpires, but I think the replay will tell the tale," Peavy said. "I was frustrated to give up that run in a way I was unhappy about. I let the first base umpire know that I wasn't happy. It's obviously a tough way to lose. I thought I had Ensberg struck out a couple of times, then he scored the winning run."
Peavy matched his career high for losses, set in 2003.
Mike Cameron hit a leadoff double for San Diego, then Pettitte retired 11 straight batters before the Padres loaded the bases with two outs in the fourth. Pettitte escaped that jam by retiring Ben Johnson on a comebacker.
Mike Piazza's single fell just in front of diving center fielder Willy Taveras, Khalil Greene hit a bouncer that eluded Everett at shortstop, and Adrian Gonzalez walked before Johnson grounded out.
The Padres had runners on first and second with two outs in the sixth before Pettitte struck out Johnson.
Pettitte was coming off a loss in relief Friday night at Arizona, when he allowed a run in the 11th inning of his first appearance out of the bullpen since 1998.
"We just caught him on a bad night," Padres rookie Josh Barfield said. "He was throwing strikes and getting us to chase pitches. We hadn't seen a guy like that all year."
Todd Walker, acquired by the Padres on Tuesday from the Chicago Cubs, grounded out on the first pitch he saw from Qualls in the seventh while pinch-hitting for Peavy. ... Walker is scheduled to start at 3B on Wednesday night. ... To make room on the roster for Ensberg, RHP Chris Sampson was optioned to Triple-A Round Rock. ... With Ensberg playing 3B, Aubrey Huff started in RF, the first time he played the outfield for the Astros. Huff was obtained from Tampa Bay on July 12 and filled in for Ensberg at 3B. ... To make room for Walker and Johnson, who came off the DL, the Padres released OF Eric Young and optioned OF Terrmel Sledge to Triple-A Portland.