ATLANTA — Ronald Acuna Jr. loves being a spark at the top of the Braves' batting order.
"It's part of my personality and the kind of baseball player that I am," he said through a translator. "That's the energy I try to bring. The energy is contagious, and I just try to make sure I bring it out there and help everyone win in that way."
Acuna hit his seventh leadoff homer of the season and scored the tiebreaking run in a four-run eighth inning to help NL East-leading Atlanta beat the Pittsburgh Pirates 5-1 on Sunday.
The 20-year-old Acuna singled off Steven Brault to begin the eighth, advanced on a bunt and scored from second on a headfirst slide after second baseman Kevin Newman errantly let Freddie Freeman's hard grounder bounce between his legs and roll into shallow right field.
Acuna's first-inning shot was his 23rd overall and tied the franchise record for leadoff homers that Marquis Grissom set in 1996.
The Braves increased their division lead over Philadelphia to four games.
Ozzie Albies kept the eighth going, chasing Brault (5-3) with an RBI single to leave the bases loaded. Dovydas Neverauskas' wild pitch to Dansby Swanson added another run, and Swanson singled to make it a four-run lead.
Julio Teheran pitched seven strong innings for Atlanta, giving up four hits, one run and two walks. He struck out five and has a 1.10 ERA in his last five starts.
Jonny Venters (4-1) got the last out of the Pirates' eighth to earn a win in relief for the second straight game.
Brault allowed four hits, one walk and three runs — one earned — in 2 1/3 innings. He struck out two.
Acuna went 3 for 4. The dazzling rookie is hitting .346 with 16 homers, 31 RBIs and 36 runs scored in 42 games since he was moved to the leadoff spot. His homer on Nick Kingham's second pitch glanced off the third-level scoreboard facade in left field.
"I'm just trying to do my part by coming out with the same energy and enthusiasm and thankfully the results have been good," Acuna said.
Kingham took the rotation spot of Ivan Nova, who is away for personal reasons, and gave up four hits and one run with four strikeouts in five innings. He did not issue a walk for the first time in his last 12 starts.
"He settled in, changed speeds, efficient with his pitches," Pittsburgh manager Clint Hurdle said. "It was a good outing."
The Pirates have scored just 46 runs since Aug. 12, the fewest in the majors over that span. They went ahead in the first when Teheran issued a pair of two-out walks and Colin Moran had an RBI single.
It didn't take long for Acuna to tie it.
"Every time he steps in the box in the first inning it's like the biggest thing for us," Teheran said. "You never know when he's going to hit a homer, but in his first at-bat it's like he's got everyone's attention, and we're waiting for that big swing."
RHP Touki Toussaint will make his second career start when Atlanta begins a three-game series Monday against Boston.
Toussaint was chosen over fellow prospects Bryse Wilson and Kyle Wright after pitching at least six innings and allowing one earned run in winning his last three starts at Triple-A Gwinnett.
The Red Sox lead the majors with 94 wins, are 50 games over .500 and rank first in the majors in runs scored, batting average and slugging percentage. It will be a big jump in competition after the Haitian-American Toussaint won his debut against the struggling Miami Marlins last month.
"You dream of this as a little kid," Toussaint said. "You want to be in the World Series pitching against the best."
The Braves announced during the game that they have reacquired OF Preston Tucker from Cincinnati for cash considerations. Tucker was dealt to the Reds on July 30 in the trade that brought OF Adam Duvall to Atlanta. Duvall, who struck out as a pinch-hitter to strand two runners in scoring position in the seventh, is batting .103 with no RBIs in 25 games with the Braves.
Atlanta RHPs Arodys Vizcaino, sidelined 53 games with right shoulder inflammation, and Jose Ramirez, sidelined 120 games with the same diagnosis, will begin rehab assignments Monday at Gwinnett and then appear Tuesday at Single-A Rome.
Pirates: RHP Trevor Williams (11-9, 3.30 ERA) will face Matt Harvey (6-7, 4.97) as Pittsburgh opens a three-game series against Cincinnati. Williams has gone 4-2 with a 0.84 ERA in seven starts since the All-Star break.
Braves: Toussaint (1-0, 1.50 ERA) will make his second career start as Atlanta opens a three-game home series against Boston. Nathan Eovaldi (5-7, 4.35) pitches for the Red Sox.