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Kris Medlen has struggled in his last three starts, but on Sunday the Atlanta Braves right-hander has an opportunity to help his team complete a three-game sweep of the St. Louis Cardinals.

The Braves have been masterful on the mound in the first two contests of this series between division leaders. Tonight, Medlen will face the Cardinals for the first time since he suffered the loss in Atlanta's wild card contest in 2012.

Medlen gave up just two earned runs in that contest and pitched into the seventh inning, but the Braves didn't give him much run support.

The same can be said for Atlanta's offense in this series thus far, even though the Braves are on the verge of completing their first three-game home sweep of the Cardinals for the first time since April 22-24, 2003.

The NL East leaders followed a 4-1 win Friday night with a 2-0 triumph yesterday afternoon.

Medlen will try to end a three-start skid tonight. In that span he's given up 24 hits and 14 earned runs covering 14 2/3 innings with losses to the Mets, Reds and Phillies. He's pitched five times in the regular season against the Cardinals, but all of those appearances came in relief.

Shelby Miller tries to win his third straight decision when he gets the ball tonight for the NL Central leaders. The 22-year-old right-hander, who will face Atlanta for the first time, blanked the Phillies over six innings on Tuesday in a 4-1 victory.

Miller is the first Cardinals rookie since Jaime Garcia (2010) to record 10 wins, and the first righty rookie since Jason Simontacchi (2002).

Andrelton Simmons' two-out, bases-loaded double in the eighth inning was the difference in yesterday's win for the Braves.

Randy Choate (1-1) started the eighth by walking Freddie Freeman. He struck out Evan Gattis before Brian McCann chased him from the mound with a base hit to center. Trevor Rosenthal fanned Dan Uggla then walked Chris Johnson to load the bases. Simmons' clutch line drive to center gave the Braves a 2-0 lead.

"I don't really feel bad about the way I pitched, it's just disappointing to leave them on," said Choate. "They just laid off some good pitches."

Luis Avilan (3-0) pitched a perfect eighth inning to earn the win after relieving Julio Teheran, who scattered just two hits over seven stellar frames. Craig Kimbrel worked a 1-2-3 ninth to collect his 30th save.

"It's a big win every time we beat a team like that," said Johnson. "We have a tremendous about of respect for the ball club over there, anytime you can beat them you're doing things right."

Matt Holliday and Jon Jay each had doubles for the only hits of the day for the Cardinals, who have lost their last two after winning four straight games.

Cardinals starter Joe Kelly, who hadn't pitched since July 12, had an effective outing. He scattered seven hits with three walks over 6 1/3 innings.

Cardinals outfielder Carlos Beltran is now 2-for-22 since the All-Star break.

The Braves won the 2012 season series, 5-1.