Pettitte got into trouble in the second when he allowed two singles and then hit Yadier Molina with a pitch to load the bases. So Taguchi followed with a two-run double on a line drive to left field, bringing Ausmus to the mound.
"Brad Ausmus came out and chewed me out pretty good," Pettitte said. "And after that I slowed down. He usually doesn't gripe very much. But he came out and griped at me a little. He kicked me in the rear."
Ausmus said, "When Taguchi got his hit on the cutter we were trying to bury it. So I wasn't happy and he had missed a couple of spots."
The talk worked and after allowing five hits in the first three innings, Pettitte went three hitless innings. In the sixth he walked Scott Rolen with one out before Jim Edmonds grounded into double play to end the inning.
The Astros are 19-9 through 28 games, the best start in franchise history, while the Cardinals have lost four straight, their longest losing streak since 2004.
Pettitte seemed relieved to get the win.
"I'm just battling myself a little," he said. "I'm just rushing in certain situations. I know what I'm doing. I've just got to keep my emotions in check."
Carpenter (3-2) was 4-0 in five starts against Houston last year, with two complete games and one shutout. On Thursday, the right-hander gave up six hits and four runs and struck out four in six innings.
"I pitched pretty well, but obviously the ball to Berkman was a mistake," Carpenter said. "We're just coming up one run short. Right now it seems we're playing just good enough to lose."
And the Astros are becoming masters of close games, 10-1 in games decided by one run.
"It seems like in this series you just know that by the end of the game it will be a one run game," Lidge said. "It's kind of the way we play them. We're real evenly matched."
Albert Pujols, who leads the majors with 15 home runs, went 0-for-4.
"Right now the offense isn't cranking, so if we make a couple of mistakes pitching we can't overcome it," Cardinals manager Tony La Russa said. "We need more consistent at-bats."
Berkman's opposite field homer to left in the fourth scored Taveras and tied the game at 2. It was the 11th home run of the year for Berkman, who leads the league in RBI (36).
"Anytime facing a guy like Chris -- such a dominating pitcher -- you want to try to get to him," Berkman said. "A lot of the time you've got to break the ice. Someone has to step up and hit the ball hard. That gave us a fresh start."
Taveras gave Houston its first lead of the night when his single scored Adam Everett in the fifth inning.
In the sixth, Morgan Ensberg got on with a double and scored when Jason Lane's high popup dropped right in the middle of Hector Luna, Pujols and Juan Encarnacion for a single. Lane's hit broke a 0-for-13 hitting slump.
The Astros lead was cut to 4-3 in the seventh when David Eckstein chased Pettitte with an RBI single to center field that was bobbled by Taveras.
Rolen returned to the lineup Thursday after missing nine games with a viral infection and had two hits, including a double.
- Pujols set the major league record for fewest team games needed to reach 15 home runs, doing it in the Cardinals' 28th game on Wednesday night, according to the Elias Sports Bureau.
- Berkman has hit safely in 11 of the last 12 games and has at least on RBI in nine straight outings.
- Houston's 14 home wins this season are the most in the majors.