MIAMI -- Fresh off a series win over the American League Central-leading Twins in Minnesota, the National League East-best Braves headed south to continue a stretch of 17 games in 17 days.

Veteran left-hander Dallas Keuchel experienced his shortest start as a Brave, but rookie righty Jeremy Walker saved the bullpen in Thursday night's 9-2 loss to the last-place Marlins to open a four-game series at Marlins Park. Ronald Acuna Jr. helped Atlanta avoid the shutout with his 30th homer of the season in the eighth against Tayron Guerrero.

• Box score

Keuchel surrendered eight runs -- the most he has given up since Aug. 8, 2017 -- on 10 hits over 3 2/3 innings to drop his third straight decision.

“I don’t think it ever gets easier giving up a bunch of runs, but one thing I can look back on is tomorrow's a new day,” said Keuchel, who permitted three homers in a start for the first time since June 5, 2018. “It’s just one of those days you’re happy the game's over with. You don’t want to say it was a letdown from a big series with Minnesota, ‘cause you don’t want to take away from the other side. They hit the ball, they scored a bunch of runs, and they started off their homestand right. We’ve got a pretty good pitcher tomorrow in Julio [Teheran], so hopefully he rights this ship for me and we get back on track.”

It seemed like a perfect matchup for Keuchel, who entered Thursday pacing the Majors with a 58.3 ground-ball percentage for starters with at least 50 innings. The Marlins lead the big leagues with a 49.4 percent ground-ball rate. Plus, Atlanta came into the series 6-0 in Miami this season.

After a leadoff infield single by Jon Berti in the first, Starlin Castro and Brian Anderson hit back-to-back homers a Statcast-projected 809 feet in total off Keuchel. A five-run fourth inning chased Keuchel following 82 pitches, with the final offering turned on by Anderson for his second homer of the day.

According to Statcast, Keuchel allowed eight batted balls in play with an exit velocity of more than 100 mph. He faced 21 batters. The eight-year veteran placed the blame on his “pretty lackluster command” of his cutter.

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"Looked like we did a pretty nice job on getting him up in the strike zone,” Marlins manager Don Mattingly said. “He’s a guy that’s really good at throwing those strikes, then working off of it, throwing the cutter in, then working off of that."

But there was a silver lining from Thursday’s series opener. After heavily relying on its bullpen over the final two games in Minnesota, Atlanta recalled Walker to provide length in case of a short start.

Walker accomplished that, pitching 3 1/3 innings and making it so the Braves needed to use just one other reliever -- southpaw Jerry Blevins -- on the night with three games remaining before Monday’s off-day.

“He did a wonderful job, because we regrouped our bullpen tonight, and he allowed us to do that,” Braves manager Brian Snitker said. “It was a great job by him. That's exactly what we needed him to do. I hate that we had to use him, but that’s what he was here for.”