Among the many skills second-year infielder Matt Carpenter has displayed for the Cardinals this season, one relatively unnoticed one is his ability to hit lefthanded pitching. The lefthanded-hitting Carpenter, batting a more than representative .294 against lefthanders, whacked his fourth home run off a southpaw out of his total of nine when he greeted Houston reliever Wesley Wright with a two-run drive in the seventh inning Wednesday night at Busch Stadium. That poke gave the Cardinals their first and only lead as they held on to beat the Astros 5-4 for their fifth straight victory, before a sellout paid crowd of 44,313. The Cardinals survived a somewhat disconcerting start by rookie Shelby Miller, who walked a season-high five in five innings. But, in the end, they had yet another save, No. 25, by rubber-armed closer Edward Mujica, who was working for the sixth game in succession, although there had been one off day. Mujica was tested after third baseman Daniel Descalso booted a potential game-ending double play ball. With two men on and one out, manager Mike Matheny visited the mound to remind Mujica to take a deep breath, to throw his best pitch and his infield would come through for him if he did. “I knew he was tired,” said Matheny, who met with Mujica in his office in the late afternoon. “He was tired before the game started. He really wanted to be in there in a save opportunity.” Pinch hitter Carlos Pena, two for four against Mujica, grounded a changeup to second baseman Carpenter, who took an instant before releasing it to shortstop Pete Kozma, who gunned the return throw to first to nip Pena. “(Carpenter) held on to it for a little extra second there,’ said Matheny. “That could have been disastrous, but Pete does a very nice job. He’s just fun to watch at shortstop.” Mujica, who has missed just one save in 26, didn’t recall having pitched six games in a row in his career. “Right now, I’m OK,” he said. “Tomorrow I might be a little tired.” After they had lost eight of 11 games, all against the American League in interleague play, the Cardinals’ five wins a row moved them back to 21 games over .500, matching their highest of the season. Left fielder Matt Holliday said, “We feel we have a good chance to win every night. I don’t think anybody even knew we lost whatever you just said.