Holliday hit two solo homers, Carpenter tossed an eight-hitter for his second complete game of the season and St. Louis beat the Houston Astros 3-1 on Saturday night.
"I felt good tonight and as the game went along I felt better," said Carpenter, who lowered his ERA to 2.10. "That was the big thing."
Holliday connected on the first pitch for each of his homers, hitting a drive to right off Wandy Rodriguez in the second and a shot to center against Jose Valverde in the eighth. He also singled in the fourth and is hitting .606 with 10 RBIs in nine games since he was acquired from Oakland on July 24.
"Sometimes you really take advantage of pitches," he said, "and I've been able to take advantage of mistakes and put them in play."
Holliday is 7 for 8 in the first two games of the series with four RBIs and three runs scored. He struck out against Jeff Fulchino in the sixth.
"If you make a pitch, you get him out," Astros manager Cecil Cooper said. "We showed that we can do that. It's just that we've not made a pitch except one at-bat the whole time."
Carpenter (10-3), who has won five consecutive decisions, struck out five and walked none in his first complete game since a 3-1 victory against Cincinnati on June 4. He allowed only one runner past first after Carlos Lee's fourth-inning homer tied it at 1.
Carpenter also doubled and scored the go-ahead run on Julio Lugo's sacrifice fly off Fulchino (4-4) in the seventh. Carpenter moved up on Humberto Quintero's passed ball before Lugo's deep fly to center.
"His hitting was more impressive than his pitching, actually more important," manager Tony La Russa said. "That's tongue in cheek, but we can't get going and he strokes a double and scores the go-ahead run. That's huge."
Rodriguez left in the fifth with a strained right hamstring. Trainer Nathan Lucero tended to the left-hander in the top of the inning after he reached on a fielder's choice. After a short talk with Lucero and Cooper, Rodriguez stayed in the game and was forced out at second when Michael Bourn hit a bouncer to shortstop.
Rodriguez, who has won a personal-best five consecutive decisions, made some practice throws in the tunnel in the middle of the inning and said his leg hurt during his follow through. He didn't come out for the bottom half.
"It doesn't hurt that much," he said. "I think I'm not going to miss the start. By how I feel today, I don't think I'm going to miss another start but we'll see more tomorrow."
Bourn was thrown out by umpire Paul Emmel in the fifth after he was cut down trying to steal second. Bourn spiked his helmet on the ground, leading to the ejection. Replays indicted Bourn was safe. ... Lee's drive was career No. 299 and just the fifth homer Carpenter has given up all season. ... Holliday has a hit in his first nine games with the Cardinals, one game short of the team record held by Charley Smith (1966) and Alvin Dark (1956). ... Cardinals slugger Albert Pujols is batting .120 (3 for 25) against Rodriguez after going 0 for 2 against the lefty. It's his worst average against any pitcher he's faced at least 20 times.