ST. LOUIS -

When Matt Carpenter trotted to right field at the start of the second inning on Wednesday, replacing Carlos Beltran, it was definitely a cause for concern for the St. Louis Cardinals Beltran, even after grounding into a double play in the bottom of the first, still had a .400 average this postseason and a .375 average in his postseason career, among the highest in baseball history.

Carpenter made certain, however, that he did more than just occupy Beltran’s defensive position and spot in the batting order – he delivered like Beltran as well. His two-run homer in the third inning sent the Cardinals on to a 3-1 win over the San Francisco Giants in the rain-delayed third game of the NL Championship Series.

The win gave the Cardinals a 2-1 series lead and raised their record to 9-1 in postseason games following a loss the last two season.

“He came off the field and I didn’t realize anything was wrong. He went underneath to put his stuff away and the next thing I knew Mike (Matheny) came up and told me to grab my glove, I was in the game in right field,” Carpenter said. “It all happened so fast, which really sometimes can be a blessing because it doesn’t give you any time to think.”

It turned out Beltran had to leave the game with a strained left knee. An MRI during the game did not reveal any structural damage, and the injury is not believed to be serious. Beltran, in fact, may play in Game 4 on Thursday.

Matheny was not surprised by Carpenter’s success, noting that he was 4-for-4 in the regular season against Cain, spread across two games, one in May and one in August.

“There are times when we are looking to see how we can get him in there,” Matheny said. “It’s a pretty strong statement with the lineup we have that there are days when we just know that he’s going to be an impact bat for us. It was nice to see him take advantage of the opportunity like he has all season.”

Carpenter became the first Cardinal to hit a home run in his first NLCS at-bat since Eduardo Perez did it as a pinch-hitter in 2002, also against the Giants.

“It really is one of those deals where you are just out there competing,” Carpenter said. “I got a good pitch to hit, and the next thing I knew I was jogging around the bases. It really was kind of surreal.

“When a guy like Carlos goes down, it can kind of be a letdown for the team and I wanted to do something that would bring some life back. That at-bat was important for what was at stake, but also to bring life back to the dugout. I was glad I could get it done.”

If Beltran can’t play on Thursday, Carpenter will be ready and the bad news for the Giants is that his parents will be at the game.

The couple drove nine hours from their home in Texas to be at the game on Wednesday, one of the few they have seen Carpenter play this season. Carpenter’s father was also his baseball coach in high school.

“They left at 3:30 in the morning to make it here,” Carpenter said. “My dad was really the guy who taught me everything I know about baseball from the time I was a little kid. They have not been at many games, but I know they were at a game in Chicago and I hit a home run that day too.”

This home run came on a 2-2 pitch from Matt Cain in Carpenter’s first career at-bat in the NLCS. He had been 1-for-5 as a pinch-hitter in the Division Series.

“It was a bad a pitch,” Cain said. “I was trying to go slider in and I didn't get it in there like I should have. I made a bad pitch and it cost us. I was trying to throw a slider that was more down and in, but it kind of stayed in the middle.”

The pitch to Carpenter was one of few mistakes on the day by Cain, but his teammates could never break through against the Cardinals, stranding 11 runners on base. Jason Motte relieved after a 3 hour, 28 minute rain delay and recorded the final six outs, in order, for the first two-inning save of his career.

“We had our chances,” said Giants manager Bruce Bochy. “We left too many on base. What you try to do in a game is create those chances. … This is a frustrating game for the fellows. They did a really good job, we just couldn’t get the line moving and get a run in.”

NOTES: Cardinals manager Mike Matheny was the catcher for Matt Cain’s MLB debut on Aug. 29, 2005 against Colorado. Matheny caught Cain a total of 14 times in 2005-06 before his retirement as a player. … The first hit Cain allowed in the majors was a home run to Matt Holliday, the fourth batter he faced. … The Cardinals played their first postseason game at home since Oct. 8, a span of nine days, having played the last three games of the Division Series at Washington and the first two games of the NLCS at San Francisco. … Adam Wainwright will start for the first time in an NLCS in game four on Thursday for the Cardinals. He pitched in three games, all in relief, and earned two saves in the 2006 NLCS against the Mets. Wainwright is 1-4 in six career starts against the Giants in the regular season, with the only win coming in his last start, Aug. 9 of this year when he gave up one run in seven innings. … San Francisco manager Bruce Bochy announced after the game that Tim Lincecum will be the starting pitcher on Thursday.