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The Atlanta Braves will try to lengthen what's already the largest divisional lead in the majors on Monday night when they host the Pittsburgh Pirates in the opener of a three-game series at Turner Field.

The Braves completed a series win over the Washington Nationals on Sunday with a 6-3 victory in Atlanta.

The win pushed their advantage in the NL East to 6 1/2 games over the Nationals, who sit in second place, and kept it at 7 1/2 games over the Philadelphia Phillies, who are third in the East.

Ironically, the Pirates, who defeated Cincinnati on Sunday to avoid a sweep, are a half-game better than the Braves thus far this season, but still sit tied with the Reds at 2 1/2 games behind the first-place St. Louis Cardinals in the NL Central.

The Cardinals, Pirates and Reds have the NL's three best records.

Tough-luck righty Kris Medlen gets the call on the mound for the Braves in his 12th start of the season after he broke out with a 10-1 mark while splitting time between starting and relieving last season.

He was 1-1 after a 3-2 win in Miami on April 9, but is 0-5 in nine starts since, though he's allowed more than three runs only twice and has pitched at least six innings six times.

The Braves dropped a 3-0 decision to Toronto in his last outing on May 29, in which he was pulled after just two innings after allowing four hits and three runs.

He pitched six innings of three-run ball against the Pirates in Pittsburgh on April 21, but lost a 4-2 verdict that dropped his career mark against the Pirates to 2-1 in five appearances.

Medlen is 0-3 in five home starts this season, though he's posted a more than respectable 2.89 earned run average.

He's opposed by veteran righty A.J. Burnett, who's also trying to end a winless stretch that's consistently featured bad luck.

Burnett was 3-2 on the season after defeating Washington, 3-1, on May 3, but he's 0-3 in five starts since.

Still, the Arkansas native has lasted seven innings in four of the five starts and give up three runs or less in all five.

The Pirates have scored 10 runs in the five games, though five of those runs came in the most recent start, a 5-3 victory over Detroit on May 29 from which Burnett got a no-decision after allowing three runs in six innings.

He's 5-11 in 20 career outings against Atlanta and is 1-2 on the road this year with a 2.70 ERA in 23 1/3 innings.

On Sunday in Pittsburgh, Travis Snider's two-out single in the bottom of the 11th inning drove in the deciding run and lifted the Pirates to a 5-4, come- from-behind victory over the Reds at PNC Park.

The Pirates, shut out in each of the first two games of this series, overcame an early 4-0 deficit. Garrett Jones knotted the score at 4-4 with a two-run homer off Jonathan Broxton in the bottom of the eighth, while five Pittsburgh relievers teamed up for 10 scoreless innings after starter Jeanmar Gomez let up four runs in the first and exited with tightness in his right forearm.

"I can't give enough credit to the job that (Bryan) Morris and (Vin) Mazzaro, (Mark) Melancon, (Jason) Grilli and (Justin) Wilson (did) at the end," said Pirates manager Clint Hurdle of his relievers. "What they were able to do, 10 scoreless innings, is quite, quite a feat."

Wilson (5-0) struck out three while working the final two frames to collect the win, with Snider and Andrew McCutchen each finishing with two hits and an RBI to aid the rally.

In Atlanta, Ramiro Pena and B.J. Upton each went deep while Freddie Freeman drove in a pair of runs to help the Braves take down the Nationals.

Justin Upton went 3-for-4 while Andrelton Simmons scored twice for Atlanta, which improved to 24-3 this season when scoring first.

Paul Maholm (7-4) hurled six innings, allowing three runs -- two earned -- on five hits while striking out four. Craig Kimbrel earned the save following two perfect innings by Anthony Varvaro and Luis Avilan, giving Atlanta relievers 17 scoreless innings on this current homestand.

"The bullpen was for me, the whole series," said Braves manager Fredi Gonzalez. "They've done their job and we've been able to add up some runs."

The Pirates took three of four from the Braves in a series played in April at PNC Park in Pittsburgh, and won the season series between the teams in 2012, 4-3. Atlanta won the 2011 series, 4-2.