ST. LOUIS(AP) Colby Rasmus got a break when third baseman Pablo Sandoval dropped his foul pop in the 10th inning. Then Bob Howry had to come after the rookie with a full count and Albert Pujols on deck.

None of that was on Rasmus' mind when he led off the 10th inning with his first game-ending home run, lifting the St. Louis Cardinals to a 2-1 victory over the San Francisco Giants . His only concern was not chasing Howry's split-fingered fastball like he did earlier in the at-bat.

''I wasn't thinking about Albert coming up or the missed popup or anything,'' Rasmus said. ''I was just trying to get a good pitch and try to do some damage with it.

''I don't think it ever really gets much better than that.''

Rasmus capitalized after Sandoval committed the Giants' third error after 10 games without a single miscue. Sandoval circled the ball off a 2-2 count against Howry (0-4), arriving late and missing with what appeared to be a casual stab with his glove.

Sandoval said he had to go around Cardinals third base coach Jose Oquendo and third base umpire Tim Tschida to get to the ball.

''But that's not an excuse,'' the rookie said. ''I have to go and catch the ball.''

Pujols was 2 for 2 after drawing intentional walks with a man on second his first two at-bats. His 26 intentional walks are more than double any other player, and he's reached safely in seven straight plate appearances.

Adam Wainwright had a career-best 12 strikeouts in nine innings for St. Louis, allowing a run and six hits. He has worked six or more innings in 15 consecutive starts. Ryan Franklin (2-0) pitched a perfect 10th for the win.

Rasmus leads NL rookies with eight homers and 29 RBIs. He also singled in the fifth in his first game back after missing two starts due to a hernia.

Rasmus is the first Cardinals rookie to hit a game-winning homer since Andy Van Slyke connected off the Astros' Bill Dawley in the 10th inning on Aug. 18, 1983. He was up there hacking, moving to 104 at-bats since his last walk May 25 and saying simply: ''I'm trying to hit.''

The Giants nearly struck him out before Howry allowed only his second homer in 28 innings all season.

''We made a great pitch and didn't get the call,'' manager Bruce Bochy said.

Rasmus wouldn't have argued.

''It was close, but in my mind I just didn't want to swing at anything down,'' Rasmus said. ''If he'd have rung me up, I wouldn't have been upset about it.''

Ryan Ludwick , a first-time All-Star last year mired in a first-half slump, drove in his first run in eight games in the first inning. The Cardinals have won only two of eight, scoring three or fewer runs in seven of those games.

Matt Cain allowed a run in seven innings for the Giants, escaping trouble in the first, third and fifth. He has worked seven innings or more in four consecutive starts.

San Francisco didn't get a runner in scoring position against Wainwright until the eighth when it loaded the bases with none out on pinch-hitter Fred Lewis ' double, an infield hit by Aaron Rowand and a walk to Randy Winn . Bengie Molina tied it at 1 with his major league-leading ninth sacrifice fly with one out before Wainwright ended the threat by striking out Nate Schierholtz .

Wainwright finished with a flourish. Edgar Renteria hit a leadoff single in the ninth and stole second as Travis Ishikawa struck out for the third time. Wainwright then struck out Juan Uribe for the third time and Lewis to end the inning.

''I just really was talking to myself the whole game: 'This is your game, you're going to finish it,''' Wainwright said. ''I didn't finish, obviously, but I took them as far as I could go.''

The Cardinals failed to capitalize on shortstop Renteria's gaffe in the eighth. Renteria threw late to second on a force attempt rather than throw to first for an easy out on slow-footed Yadier Molina 's grounder, loading the bases with two outs, but Sergio Romo struck out Joe Thurston .

NOTES: Wainwright's strikeout total is the Cardinals' best for a nine-inning game since Chris Carpenter fanned 13 on June 13, 2006, at Pittsburgh. ... Injured Mark DeRosa is 0 for 9 in three games with the Cardinals and 2 for 27 with one RBI since June 20. ... Pujols is 5 for 9 with a homer, four RBIs and three walks against Cain.