The Atlanta Braves are starting to run away in the NL East and can pad their lead some more when they start a three-game series with the Philadelphia Phillies Friday at Citizens Bank Park.

The Braves are 11 1/2 games ahead of Washington and 13 1/2 games in front of Philadelphia for division supremacy and will play their next 17 games against NL East foes. They will visit the Nationals next week before taking on Miami, Philadelphia, Washington and New York.

Atlanta recorded its seventh straight win with Thursday's 11-2 pounding of the Colorado Rockies in the finale of a four-game series at Turner Field. Justin Upton homered twice and drove in five runs, while Jason Heyward went deep. Chris Johnson added three hits and two RBI for the Braves, who got five innings of one-run ball and 11 strikeouts from Julio Teheran.

"I was trying to make my pitch, using my four-seamer," Teheran said. "It was coming out good from my hand. I felt pretty good."

Kris Medlen gets the nod for the Braves Friday night and halted a personal three-start losing streak his last time out versus St. Louis on Sunday. In the 5-2 win over the Cardinals, Medlen held the visitors to two runs in six innings and is 7-10 with a 3.74 ERA in 21 starts.

Medlen lost to the Phillies on July 7 when he gave up seven runs (6 earned) in a 7-3 road loss and is 1-2 with a 5.82 ERA in 15 career games (4 starts) against them.

Philadelphia lost two of three meetings with the San Francisco Giants to start a nine-game homestand and sustained a tough 2-1 loss on Thursday. After Cole Hamels hurled eight shutout innings with a 1-0 lead, closer Jonathan Papelbon blew his sixth save of the season by allowing two runs in the ninth.

"I still think he's a really good closer," Phillies manager Charlie Manuel said of Papelbon. "He gave up four hits in a row, but none of them were really scorched. He was using all of his pitches, they were just finding holes."

Hamels drove in the lone run for the struggling Phillies, losers in 10 of their last 11 games. The Phils halted an eight-game slide Tuesday.

Ethan Martin will make his major league debut on the mound for the Phillies Friday and went 11-5 with a 4.12 ERA in 21 starts with Triple-A Lehigh Valley. Martin has pitched 115 2/3 innings for the IronPigs this season and the right- hander was a first-round pick back in 2008.

Martin is taking the place of All-Star left-hander Cliff Lee, who is nursing a sore neck.

"I want to come up here and show what I got and prove to them that I can be here," Martin told the club's website. "If Cliff comes back and it's my time to go back down, I want to show to them and put it in the back of their heads whenever they need somebody else."

Philadelphia and Atlanta have split six meetings this season.