ATLANTA -- Chris Johnson believed he was overdue for a two-out hit with runners in scoring position.
He came through with a bases-loaded hit that helped turn a tie game into a rout.
The Braves set a season high with 16 hits and matched their high for runs.
Johnson was hitting .320 with two outs and runners in scoring position, according to STATS LLC. He only remembered the failed opportunities.
"I've not gotten the guy in this year when it was my turn to do that," said Johnson, who had three hits to lift his average to .330. "I was just trying to pick up the guys in front of me and I think that's the mark of a good ballclub."
The game was tied at 3 before the Braves opened the sixth with three straight hits off Dan Jennings (0-1), loading the bases. Ryan Webb struck out Dan Uggla and Reed Johnson before Chris Johnson gave Atlanta the lead with his double past first baseman Logan Morrison.
Jordan Schafer and Andrelton Simmons added run-scoring infield singles to cap the big inning.
The Braves had five doubles and two triples but no home runs.
"I thought the biggest double was Chris Johnson's," manager Fredi Gonzalez said. "It looked like they were going to get out of that inning. It was a pretty good at-bat. He snuck that ball just inside the first-base line."
Marlins manager Mike Redmond said Webb almost pitched out of the bases-loaded jam.
"It was a tough situation for him to come in, first of all, but he did a great job and almost got out of it," Redmond said. "Really, one pitch. And after that, the flood-gates kind of opened up."
Webb said he "wouldn't take back any pitch I threw."
"Nothing I can do about it," Webb said. "I did my job. I got the strikeouts, I got the ground ball."
Morrison hit a two-run homer in the first inning.
Kris Medlen (6-7) gave up three runs and nine hits and two walks in six innings as the NL East-leading Braves took their fourth straight win.
"I just tried to keep us close and not give away too many leads and wait for the big inning," Medlen said. "That's exactly what happened today."
The Marlins' three-game winning streak ended. Miami committed two errors and left nine runners on base.
"We were sloppy today," Redmond said. "Sloppy in all aspects of the game. Defense, especially, but pitching, late in the game we made some dicey pitches. Offensively we had some chances but we just couldn't get that big hit.
"As well as we've played, it's disappointing that we didn't play better tonight and that we played so sloppy collectively."
The Braves added three runs in the eighth. Justin Upton and Brian McCann, who each had three hits, had run-scoring singles in the inning. Johnson also had three hits. Andrelton Simmons tripled in a run.
McCann also had a run-scoring double in the seventh.
Miami rookie right-hander Tom Koehler gave up three runs, two earned, and five hits in five innings.
An error by Marlins left fielder Juan Pierre helped the Braves break a 2-2 tie in the fourth. Justin Upton led off the inning with a triple to right field. Freddie Freeman followed with a fly ball between Pierre and center fielder Marcell Ozuna.
Both outfielders hesitated before Pierre made a late try for the ball, which fell off his glove for the error. Upton scored for the 3-2 lead.
Pinch-hitter Greg Dobbs' two-out single off Medlen in the sixth drove in Derek Dietrich for a 3-3 tie.
Braves center fielder B.J. Upton left the game after the second inning with left forearm spasms. The Braves say Upton's status is day to day.
The Marlins survived an injury scare in the third inning when Morrison was upended at first base when reaching for a wild throw by third baseman Placido Polanco on Medlen's grounder. Morrison fell over Medlen and landed hard on his right side. Medlen was safe on Polanco's error.
Braves first base coach Terry Pendleton immediately signaled for help from the Marlins' dugout as Morrison, who missed the first two months of the season recovering from right knee surgery, remained on the ground. Morrison finally was helped to his feet and remained in the game.
Medlen came out of the collision with a scrape on his right arm.
Schafer made his first appearance since fouling a ball off his right ankle on Wednesday, and he was limping after his pinch-hit single. ... Braves RHP Cristhian Martinez, on the DL since April 7 with a right shoulder strain, said he's still having pain. Martinez returned to Atlanta to have the shoulder examined. ... Gonzalez said C Evan Gattis, on the 15-day DL since June 18 with a right oblique strain, is improving but is not ready for baseball activities. ... Marlins RHP Ricky Nolasco, 5-10 with a 5.26 ERA in 23 career appearances against Atlanta, will face LHP Mike Minor as the three-game series continues on Wednesday night. ... Redmond said other starters will have their next starts pushed back a day to make room for RHP Henderson Alvarez, who will make his 2013 debut on Thursday night.