ATLANTA — With Miami's playoff hopes getting slimmer, Tom Koehler was frustrated that he didn't pitch well enough to beat the Atlanta Braves.
Koehler earned no decision as Miami's bullpen struggled in Atlanta's three-run seventh inning and the Marlins lost 5-2 on Friday night.
"I put this game on me," Koehler said. "The team did a great job, played solid defense behind me all day. To kind of just give up two runs right there and put us back in a hole, that's unacceptable."
In six career starts and three relief appearances against the Braves, Koehler is 0-2 with a respectable 3.15 ERA, but that's not enough to satisfy him.
Justin Upton homered and had three RBIs for the Braves, and Jason Heyward drove in the go-ahead run in the seventh inning.
The Braves, winners of three straight and 10 of 14, began the night 1 1/2 games back in the wild-card standings, but are just 19-21 since the All-Star break. Miami trails Atlanta by five games.
Andrelton Simmons led off the seventh against Chris Hatcher (0-2) with a bunt single and advanced to third on pinch-hitter Ramiro Pena's single.
Simmons scored on Heyward's RBI single off Mike Dunn to give the Braves a 3-2 lead. Upton's RBI single off Sam Dyson drove in Heyward from second and Emilio Bonifacio also scored to make it 5-2 when center fielder Marcell Ozuna misplayed the ball.
"We've got to play defense," Miami manager Mike Redmond said. "We've got to make plays. We had a couple opportunities to make some plays and didn't and that cost us."
Jordany Valdespin tied it at 2-all in the Miami seventh with a pinch-hit homer, the seventh of his career, off reliever David Carpenter (5-3).
Braves starter Ervin Santana allowed one run, five hits, four walks and struck out seven in six innings.
Koehler walked Freddie Freeman to begin the sixth and gave up Upton's 26th homer, a long shot deep into the seats in left-center, for a 2-1 Atlanta lead.
"There's only so many fastballs Justin's going to miss," Koehler said. "Unfortunately, that wasn't one of them. Every mistake right now is going to be magnified, because we're playing for something."
Koehler gave up two runs and four hits with three walks and six strikeouts in six innings.
The Marlins have dropped three straight and five of six.
Santana needed 32 pitches to finish the first inning, walking three straight batters to load the bases, but escaped the jam by striking out Garrett Jones on three pitches and retiring Ozuna on a flyout.
In the sixth, Ozuna doubled into the right-field corner off Santana, scoring Casey McGehee from second to make it 1-0, but Garrett Jones was thrown out at the plate on second baseman Tommy La Stella's relay throw to catcher Evan Gattis.
Marlins: Redmond said that RHP Dan Jennings, out since Aug. 8 with a concussion, was making a rehab start Friday and could rejoin the team soon.
Braves: LHP Jonny Venters, who last pitched in 2012, said that he will undergo elbow ligament replacement surgery for the third time and added that "it never crossed my mind" to retire.
Marlins RHP Jarred Cosart (11-8) beat the Braves 6-1 on June 26 while pitching for Houston.
Braves RHP Aaron Harang (10-8) is winless with a 5.18 ERA in four starts this year and 5-5 with a 5.99 in 17 career starts against the Marlins.
Closer Craig Kimbrel, the fourth Atlanta pitcher, earned his 40th save in 44 chances after facing the minimum in the ninth. ... The Braves improved to 69-44 dating back to last season with Heyward batting leadoff. ... Upton went 2 for 4 and is hitting.307 with 10 homers and 45 RBIs in his 52 games since the start of July. His 91 RBIs this year are a career high and three better than he had in 2011 with Arizona.
"Every night's not going to be a three-run homer," Upton said. "We're going to have to find ways to scratch runs across. We did that tonight."
Atlanta 1B Freddie Freeman went 0 for 3 and his hitting .056 in 54 at-bats against the Marlins this season. ... Jones dropped to 1 for 12 with the bases loaded this year. ... Braves CF B.J. Upton was out of the lineup for the fourth time in seven games. After hitting a modest .255 in 98 at-bats in July, he's hitting .115 in August.