ST. LOUIS -- Skip Schumaker was so excited he almost made a very big mistake. Not the kind of mistake that haunts you in the clubhouse, but one much worse -- one that would have come back to bite him when he went home to celebrate the biggest hit of his career.

Schumaker poked the first walk-off home run of his career, a two-run shot in the 11th inning, to give the Cardinals a 5-3 win over the Cubs. Asked about the feeling, he slipped up, but only briefly. Then he caught himself.

"I had a kid this offseason, and [the home run] is next," he said, momentarily leaving out one other big moment. "That was the best time for me in the big leagues by far. The walk-off [single] a couple days ago was a good feeling, but this was incredible. I'm at a loss for words.

"Other than having a kid and getting married -- should mention that one -- obviously the walk-off is the best."

Fortunately for Schumaker, mistakes like that are getting rarer and rarer. He keeps his poise on the field and off. A player who looked overwhelmed in 2005 and 2006, and who surprised with his performance in 2007, now simply looks like he belongs.

It was no surprise, then, when Schumaker delivered his second game-ending hit in less than a week. On Saturday, he hit a single against the Astros to make the Cardinals winners. The only surprise on Friday was that he hit a home run, rather than another single or a sacrifice fly.

"I never think they're home runs when I hit 'em," Schumaker said. "I don't hit enough to know that they're home runs. You want to get a pitch up in that situation. I was looking for a pitch up over the middle of the plate. I got lucky to get the barrel on it and hit it in the air."

In a familiar pattern for the Cardinals, pinch-hitter Aaron Miles opened the winning rally with a bloop single into left field. Miles took second base on a wild pitch, and Brendan Ryan bunted Miles over to third.

With only one out, all Schumaker had to do was get a ball into the outfield for a sac fly. He did that, and then some. The ball hit the top of the outfield wall and bounced over for the fifth home run of Schumaker's career.

Ron Villone got the win for 2 1/3 shutout innings of relief. Villone escaped a two-on, two-out jam when he relieved Jason Isringhausen, who struggled once again. Isringhausen took his third blown save of the year, allowing a two-run homer to Alfonso Soriano in the top of the ninth.

Villone pitched a perfect 10th before having some trouble in the 11th. He allowed a leadoff single, then retired the next two batters. He pitched around Derrek Lee, walking the star, before getting a groundout from Mike Fontenot.

"He is a really good competitor and he'll do anything out of that bullpen," said Cardinals manager Tony La Russa. "He gets into that game. He reminds me a lot of [Troy] Percival. They come in and they know it's your club trying to get the other club and you've got to get the hitter out. That was outstanding. That was huge what he did today."

Isringhausen, meanwhile, has been scored upon in five of his past eight outings.

"I feel great physically," he said. "I'm just struggling very badly right now. That's all I can say. I feel good. I make some good pitches, and then I make a bad pitch that ends up getting hit."

Cubs starter Rich Hill walked four of the six batters he faced and didn't make it out of the first inning, but the Cardinals could muster only one run in the top of the first. They added another tally in the second when Brendan Ryan singled home pitcher Adam Wainwright.

After that, however, it was tough going against a string of Chicago relievers. St. Louis didn't score another run until the seventh, when an error and two Soriano misplays led to a tally. Yadier Molina was credited with an RBI double when Soriano simply failed to glove his fly ball to the warning track.

Wainwright turned in a fine game, pitching 6 1/3 innings of four-hit, one-run ball. He struck out five and walked one. Coming off a career-high 126-pitch effort six days ago against Houston, Wainwright pitched fewer than seven innings for the first time this year.

"I think my arm was given plenty of time to rest," Wainwright said. "The important thing is to not push it too early. We're just getting out of April here. It's good to be a hero, but not all in the first month."

The Cardinals have won three straight and five out of six to improve to 19-11 on the year. They lead the second-place Cubs by 1 1/2 games in the National League Central.