HOUSTON (Ticker) -- Houston Astros manager Phil Garner wanted to get Chris Burke into the lineup. He made the right decision by not having him replace Mike Lamb .

Lamb hit a two-run homer and scored the go-ahead run in the sixth inning as the Astros took a two games to one lead in the National League Championship Series with a 4-3 victory over St. Louis Cardinals.

A part-time player during the regular season, Burke earned more playing time after going 5-for-8 with two homers and four RBI in the playoffs. The rookie had platooned with the lefthanded-hitting Lamb, with Lance Berkman alternating between the outfield and first base.

However, Burke started in center field for just the second time in his career in Game Three, replacing Rookie of the Year candidate Willy Taveras and allowing Lamb to face Cardinals starter Matt Morris , a pitcher against whom he has fared very well in his career.

"It stinks that there's got to be an odd man out," Lamb said. "It stinks today that Willy Taveras did not get a chance to start. There has to be an odd man out. Today was Willy and tomorrow it could be me, who knows?" After Morris walked Morgan Ensberg to open the fourth, Lamb belted 2-1 pitch over the left field wall for a 2-0 lead.

A pair of sacrifice flies tied the contest before Lamb hit a double off Morris with one out in the sixth and scored on Jason Lane 's single a batter later to make it 3-2.

" Mike Lamb has had my number," Morris said. "He came up, and I made a mistake with the cutter, and he hit it for the double. I was trying to go in on him, and he slapped it to right. There's your 3-2 ballgame."

Including the postseason, Lamb is 8-for-18 with five home runs in his career against Morris.

"For whatever reason, it seems that I see the ball well off him," Lamb said. "I have a lot of respect for him and he is a 20-game winner that has been in the league a long time. He's a great pitcher and I think that when we're both done with our careers, he is going to be the one that will be remembered."

"Matt has weapons. Matt can get Lamb out," Cardinals manager Tony La Russa said. "If a guy has numbers like that, he's got more confidence and he's a tougher out."

Lane went to third on Brad Ausmus ' base hit and collided with St. Louis third baseman Abraham Nunez , who left the game with a bruised left thigh.

"I went around and I saw him moving into the line to get the ball, so I just went down and tried to get down and underneath to try to get to the base," Lane said. "I clipped his leg and broke the play up. ... Hopefully, it's not too bad."

St. Louis already was playing without left fielder Reggie Sanders , who suffered a sprained lower back in Game Two.

"I don't see (the injuries) as a disadvantage," Garner said. "It may not be exactly as they would like to have it. Still, they are a very good ballclub. We are not going to take anything for granted."

Hector Luna replaced Nunez at third and immediately committed a throwing error, allowing Lane to score.

"The ball didn't slip out of my hand," Luna said. "I just got it at a high position, and it was a tough throw to make."

Roger Clemens (2-1) yielded two runs and six hits in six innings, throwing 62 of 97 pitches for strikes.

The seven-time Cy Young Award winner cruised through the first three frames before issuing a pair of two-out walks to Jim Edmonds and Larry Walker in the fourth. Clemens got Mark Grudzielanek to ground out to end the threat, but did not escape unscathed in the next two innings.

"Sometimes this time of year, you have to will yourself through some innings," Clemens said. "I'm just real fortunate. It's a battle."

The Cardinals got consecutive singles against Clemens to open the fifth and the sixth, but managed one run in each inning on sacrifice flies from David Eckstein and Walker.

"We had some balls that we got on the barrel," La Russa said. "Sometimes a good pitcher will let you do that with nobody on, and all of a sudden guys got on we didn't have a lot to hit at."

"He bent a little bit, but he certainly didn't break and he didn't give in," Garner said. "He had given up a couple of runs, but still did a terrific job for us." Chad Qualls struck out three in two perfect innings and Brad Lidge surrendered a run in the ninth before getting Eckstein to fly out to shallow center field with a runner on second base to notch his second postseason save.

"We definitely had a chance to win today," Eckstein said. "We had runners out there and had a chance to tie the ballgame up. We were trying to find a way to win."

It was the first time the Cardinals have scored against Lidge in over two years.

"They are just too good to keep down forever," Lidge said. "They are going to score a run here or there and the whole thing is to come back strong and finish the game. They were able to get one, but we won the game and that is what I am most happy about right now."

Morris (1-1) allowed four runs - three earned - and eight hits in 5 1/3 innings.

The Astros will try to move one step closer to their first World Series appearance in Game Four here Sunday. Brandon Backe will start for Houston against Jeff Suppan , who has not pitched since September 25.