HOUSTON -- The Astros had seen the scoreboard indicating the Braves had suffered another loss and knew what that meant to the Cardinals. They could hear the large contingent of red-clad fans getting louder with every charge St. Louis mounted.Don't tell the Astros they had nothing to play for. The Astros put their imprint on the National League playoff race by pushing across the game-winning run in the 10th inning Monday night when Angel Sanchez put down a squeeze bunt to score Brian Bogusevic and send Houston to a 5-4 win at Minute Maid Park. "It was a pretty lively crowd for a Monday night, so it was fun," Bogusevic said. "Winding down the season and we're not in the playoff race, but to have the game be meaningful is fun for us." The Astros prevented the Cardinals from pulling even in the NL Wild Card race with the Braves. With two games remaining, St. Louis trails Atlanta by one game for the final playoff spot in the NL. "It's disappointing because we got beat, but there's nothing else about it," St. Louis manager Tony La Russa said. "I thought our effort was outstanding. Created a lot of situations, made a lot of plays, and they beat us. So what you do is you put everything into it, and if the other team beats you, you tip your cap. Period." Mark Melancon, whose wife was scheduled to be induced into labor following the game, threw two scoreless innings to get the win and improve to 8-4. His eight wins are the most for an Astros reliever since Doug Henry won eight in 1998. "We didn't get to his spot and we told him to go back out, and he did a good job of getting us back in in a hurry," Astros manager Brad Mills said. "He came to me and said, 'It's almost 10:30.' I said, 'Go have a baby.'" Cardinals slugger Lance Berkman came back to burn his former team yet again when he lined a two-run double off the left-field wall in the eighth inning to tie the game at 4. Enerio Del Rosario came out of the bullpen and got the final three outs of the eighth to get the ball to Melancon. Bogusevic led off the 10th against Octavio Dotel with a pinch-hit double to left field, and Jason Bourgeois pushed him to third by putting down a bunt that Dotel couldn't handle. Sanchez, who had 10 sacrifice bunts entering the game, put down a squeeze bunt toward first base. "I'm a pretty good bunter and it was easier that he threw me a slider and it was easier to get down," Sanchez said. Bogusevic didn't start running until the ball was put in play, and Dotel allowed it to roll under his glove, enabling Bogusevic to slide home with the winning run. "It's a fun play, being on the bases," Bogusevic said. "It wasn't a suicide. You kind of have to make a little read, but it's exciting when you know it's coming and you know once you get read that it's down and you've got to go. I enjoyed it." The Astros escaped a jam in the top of the 10th when Yadier Molina doubled with one out and was thrown out at third on a comebacker to the mound. Astros catcher J.R. Towles then threw out Ryan Theriot trying to steal to end the inning. Astros starter Wandy Rodriguez held the Cardinals to eight hits and two runs in 6 1/3 innings and left the game with a 4-2 lead. He was poised to finish the season with a winning record before Berkman's double gave him 14 RBIs this year at Minute Maid Park in seven games. "Wandy battled through the whole thing," Mills said. "He had some runners on and kept working around them, and the bullpen did a good job." The Astros took a 2-1 lead in the second when Rodriguez scored Clint Barmes with a sacrifice bunt and Bourgeois ripped a double to left field. Matt Downs, getting another start in right field, hit a towering two-run homer to left field in the fourth off Cardinals starter Jaime Garcia to make it 4-1. "He left a fastball up and I got a good bit of it," said Downs, who has 10 homers in 199 at-bats. "He had good stuff first time around, but the second time around I don't know if he got tired or what. He just got the ball up in the zone a little bit that inning." St. Louis loaded the bases with no outs in fifth, but Rodriguez got David Freese to hit into a double play and struck out Albert Pujols swinging. Berkman got the Cardinals back into it a few innings later, but that only set the stage for the Astros' ninth walk-off win of the year. "You know what's riding on the line, everybody knows what's riding on the line with the games," Downs said. "I wouldn't say it's a playoff atmosphere because of the crowd, but it's always good to shut up their crowd at home. They got more fans than we do, so it's always fun to shut them up when we're at home."