St. Louis ? Remember this chant from postseasons long ago?

“Reggie! Reggie! Reggie!”

There’s a new Mr. October in the baseball playoffs, and that first name sure sounds familiar.

Reggie Sanders kept up his torrid postseason with a two-run homer and Chris Carpenter grounded Houston’s offense, leading the St. Louis Cardinals past the Astros 5-3 in Game 1 of the NL championship series Wednesday night.

“Everything is about timing,” Sanders said. “I’m just out there doing my thing.”

The Cardinals extended the pattern of home-field dominance that held throughout last year’s NLCS against the Astros. The home team won every game, giving St. Louis a seven-game victory and a trip to the World Series.

In the league’s first championship rematch since 1992, the Cardinals again got the upper hand on their division rival, a team they finished 11 games ahead of in the NL Central. They have to get by the Astros again for a chance at World Series redemption after their four-game sweep by the Boston Red Sox in 2004.

Game 2 is tonight. Houston’s 20-game winner, Roy Oswalt, goes against Mark Mulder of the Cardinals.

The wild-card Astros got off to a poor start before the series even began. While running the bases in batting practice, starting pitcher Andy Pettitte was struck on the inside of the right knee with a sharp liner.

St. Louis left fielder Reggie Sanders, left, accepts congratulations from teammate Larry Walker after catching a deep fly ball hit by Houston's Mike Lamb. Sanders hit a two-run homer in the Cardinals' 5-3 victory Wednesday night in St. Louis.

The Astros insisted the left-hander was fine, but he sure didn’t look like a pitcher who was 17-9 with the NL’s second-lowest earned-run average (2.39) during the regular season. Afterward, Houston came clean.

“It swelled up on him and that was probably a little factor in the game,” manager Phil Garner said. “He was trying to pitch through it.”

Pettitte finished batting practice, then ducked into the clubhouse for treatment.

“It was a freak accident,” he said. “I saw it the whole time. I tried to jump over it, but it hit my knee.”

Pettitte exceeded his regular-season ERA in the first two innings. Sanders hit his mammoth shot in the first, and St. Louis made it 3-0 in the second on Carpenter’s squeeze bunt, a familiar offensive weapon for the small-ball Cardinals.

Sanders, a flop in five previous postseasons, has resembled Reggie Jackson this time around. The 37-year-old outfielder had a homer and 10 RBIs in a three-game sweep of the San Diego Padres in the opening round, including a division series-record six RBIs in the opener.

He didn’t take long to get going in the NLCS. With two outs and a runner at first, he fell behind 1-2 but jumped on the next pitch, a fastball left over the plate. Sanders sent a 445-foot drive that just missed the scoreboard hanging above the auxiliary press box. Left fielder Lance Berkman barely moved.

As Sanders trotted out to play left field in the top of the second, the fans who had just gotten an up-close look at the homer serenaded him with chants of “Reggie! Reggie! Reggie!”

For good measure, Sanders also made a leaping catch against the wall on Mike Lamb to end the sixth. Once again, the crowd erupted in chants of “Reggie! Reggie! Reggie!”

Before this year, Sanders’ postseason resume was dismal: 36-for-191 for a .188 average, with five homers and 13 RBIs.

“This is such a big magnifying glass,” said Sanders, who has bounced around with seven teams in the last eight years. “Everything is heightened when you come through in key situations.”