In his first outing since he left his April 19 start with a strained groin, Rodriguez yielded three unearned runs in the opening frame and couldn't make it out of the fifth inning as the Astros lost to the Cardinals, 6-1, Wednesday night at Busch Stadium.

The Astros' defense contributed to this loss, as did the offense, which was practically non-existent against Adam Wainwright, who dominated Houston for the second time this year as he coasted to his fifth win. Wainwright yielded a Ty Wigginton solo homer in the second but retired 17 of his next 18 batters before J.R. Towles reached on a Cesar Izturis error in the eighth.

"[Wainwright] pitched well," manager Cecil Cooper said. "We didn't hit many balls hard. The same thing happened to us [Tuesday] night -- they gift-wrapped a few for us in the first and we did the same thing to them. You can't spot them runs, especially if the guy's a quality pitcher. He was good tonight."

The Astros logged only four hits all night -- Wigginton's homer, a two-out single by Miguel Tejada in the first, a triple by Michael Bourn in the third and an infield single by Lance Berkman off Chris Perez in the ninth.

"[Wainwright] was lights-out from the get-go," Wigginton said. "He left that one [home run ball] up in the zone. That was really the only pitch he left up in the zone all night."

Wainwright has allowed four earned runs to the Astros this year, all solo homers. He is unbeaten in his career versus Houston -- he has four wins and a 2.18 ERA over 11 games, including five starts.

The Astros matched a season low with four hits. They scored the fewest amount of runs since their last trip to Busch Stadium a month ago, when they scored one run in a 5-1 loss to the Cardinals April 27.

As soon as Rodriguez threw the first pitch, he was in trouble. He yielded a base hit to leadoff man Brendan Ryan, who then made it to third when Kazuo Matsui threw wide to Tejada on a Rick Ankiel ground ball. Instead of getting the double play, Rodriguez was in a bases-loaded, no-outs situation after he issued an intentional walk to Albert Pujols.

"I caught the ball and it was kind of low," Matsui said through an interpreter. "If I threw low, it was going to go lower. I tried to lift it up a little bit, but then the ball flew over [Tejada]."

The intentional walk to Pujols backfired when Rodriguez walked Ryan Ludwick on four pitches and let another run score on a wild pitch.

"I'm a little disappointed in the fact we have a four-pitch walk and we didn't get close to the strike zone," Cooper said. "We were trying to just limit the damage. Some of that can be chalked up to [Rodriguez] not being out there for a long time."

Rodriguez, who missed six starts during his stint on the DL, yielded two more runs in the fourth after Yadier Molina and Brian Barton logged back-to-back leadoff singles. Izturis sent a triple to deep center, scoring both baserunners. The Cardinals tacked on one more in the fifth behind a Molina RBI single.

Rodriguez threw 27 pitches in the opening frame and had thrown 76 through four. His pitch count had reached 92 by the time he was lifted in the fifth, after Molina's single.

Rodriguez said physically, he felt "excellent." But he also acknowledged that he didn't have his good curveball working, while Cooper also noticed his changeup wasn't fooling anyone, either.

"I thought he did fine, considering the layoff and time off," Cooper said. "He just didn't have his breaking ball tonight. If he had his curveball, maybe it would have been a different story."

"I don't know what happened," Rodriguez said. "I need to work on it, because I need my curveball."