HOUSTON — Brooks Conrad's two-run homer in the ninth inning powered the Atlanta Braves to a 4-2 win over the Houston Astros on Tuesday night.

The Braves were trailing 2-1 after the Astros scored a pair of runs in the eighth inning off Atlanta errors before Conrad's shot to right field off Houston closer Matt Lindstrom (2-3).

Alex Gonzalez singled to set up Conrad's go-ahead shot. Conrad entered the game in the bottom of the sixth inning to replace Chipper Jones, who sprained his left knee.

Troy Glaus added a solo homer in the ninth and also drove in Atlanta's first run in the seventh inning.

Jonny Venters (4-0) got the win after striking out Jason Michaels to end the eighth inning and Billy Wagner pitched a perfect ninth for his 28th save.

Atlanta's big ninth inning allowed the team to overcome another sloppy defensive night. The Braves committed three errors for the second straight game.

Michael Bourn tripled in the eighth inning and tied it on an error by Gonzalez on a bad throw home to Brian McCann on a ball hit by Jeff Keppinger. Keppinger reached first on a fielder's choice. Braves starter Jair Jurrjens then intentionally walked Hunter Pence and was replaced by Peter Moylan.

Houston went ahead on an error by Omar Infante when he missed the catch at second, allowing Keppinger to score.

Glaus put Atlanta up 1-0 with an RBI-single in the seventh inning. Astros starter J.A. Happ set up that score by walking Conrad to start the seventh before walking McCann with one out.

Jurrjens allowed six hits and two runs in 7 1-3 innings.

Happ did not factor in the decision, but was much better on Tuesday than in his last start where he allowed seven earned runs in one-plus innings. He yielded just two hits and a run in 6 1-3 innings in his third start for the Astros since being traded from Philadelphia for Roy Oswalt.

Rick Ankiel robbed Carlos Lee of a hit with one out in the fourth inning with a nifty diving grab on his fly ball to center. Ankiel dove headfirst to snag the ball and bounced awkwardly on the grass as he landed with his glove between his legs, but with the ball sitting firmly in it.

Chris Johnson singled after that but Jurrjens struck out Brett Wallace to end that inning.

Jason Castro singled in the fifth inning before Happ reached on an error by Jones. But Jurrjens retired the next three Astros to end the inning.

Happ retired the first seven batters he faced before walking Ankiel with one out in the third inning. But he got out of that inning unscathed after striking out Jurrjens before Ankiel was picked off trying to steal second base.

He didn't allow a hit until a double by Jones with two outs in the fourth inning. Happ intentionally walked Matt Diaz before McCann popped out for the third out.

He sailed through the next two innings, facing the minimum in the fifth and sixth, before the walk to Conrad to start the seventh. The run-scoring single to Glaus chased Happ.

He was replaced by Wilton Lopez, and the Astros turned a double play to limit the damage.

Jones was injured fielding a ball in the sixth inning. He grabbed a grounder hit by Pence and jumped in the air as he made the throw to first base to get Pence out. He then fell to the ground where he remained for several minutes while trainers and coaches crowded around him. He was helped to his feet and walked gingerly off on his own power.

NOTES: Right fielder Jason Heyward was scratched from Atlanta's lineup because of a sore right knee. ... The Astros presented Braves manager Bobby Cox with a cowboy hat and a pair of boots to honor his career before the game. Houston manager Brad Mills and hitting coach Jeff Bagwell handed him the gifts. ... Cox chatted with Orlando Magic coach Stan Van Gundy and his brother former Houston Rockets and New York Knicks coach Jeff Van Gundy in the dugout before batting practice on Tuesday.