MIAMI -- Things unraveled for Marlins starter Caleb Smith in the fifth inning and Miami never recovered, falling 8-4 Friday to Atlanta, which evened the four-game series at one apiece.

Don Mattingly was ejected for the 32nd time in his managerial career. The hook came in that fateful fifth inning when Smith, pitching to opposing starter Julio Teheran with runners on first and second and no outs, was called for a balk.

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An irate Mattingly exited the dugout and walked towards second-base umpire John Tumpane, who tossed him after a brief but heated discussion, and within two batters the Braves increased their one-run lead to a 4-0 advantage. Teheran, no longer in need of bunting the runners over, instead lifted a sacrifice fly to score one run.

“I’m not sure what their interpretation was,” Mattingly said. “I really don’t know what they called. It looked like the hitter backed out [of the batter’s box] first. And then I see the umpire’s hands go up. I’m sure the league will look at it, but if that’s a balk, there’s probably a balk every game.”

Ronald Acuña Jr. (3-for-5) crushed the next pitch for his first of two two-run homers on the night and Smith (7-6) never made it out of the inning. Four singles later, the Braves scored twice more to take a commanding 6-0 lead. Acuna’s two-run homer in the ninth off Austin Brice put the game out of reach.

“He’s a special talent,” Mattingly said. “He hit a breaking ball, he hits a high fastball. He’s a guy that handles a lot of pitches.”

Smith had not given up more than six hits in a game this season. But in that unnerving fifth inning, he allowed seven hits and five runs. Oddly enough, the fifth inning had been Smith’s best this season, previously giving up just one run all season in that frame.

“I asked [the umpire] what I did, and he said I moved my shoulder,” Smith said of the balk. “As far as I know, when I’m not set, I can move my shoulder as much as I want. I didn’t balk.”

In his shortest stint since May 26, Smith yielded six earned runs and 10 hits, both career highs, in 4 2/3 innings of work.

“That call changes the entire game,” Smith said. “I just leave some pitches out over [the plate] that got hit. After [the balk was called] there’s nothing you can do about it so there’s no point in dwelling on it. So that wasn’t really in my mind. 

“I was just trying to make pitches after that and I wasn’t able to. I left sliders over the middle of the plate, and they hit the ball hard. Same with fastballs, Acuna hit a fastball that was middle up. He did damage with it. They’re a good lineup.”

Starlin Castro got the Marlins on the board in the seventh with a rainbow solo homer, his 11th of the season. He and Robinson Canó are the only middle infielders in the Majors to hit 10-plus homers in nine consecutive seasons.

“Obviously he’s swinging the bat well,” said Mattingly of Castro, who had a season-high four hits and homered in consecutive games for the first time since April 1-2 against the Mets.

Aside from that, the bright spot for the Marlins was three perfect innings of relief work from left-hander Wei-Yin Chen, who struck out three.