Donaldson homered twice and drove in four runs, Ronald Acuna Jr. had a 455-foot shot and Keuchel pitched seven strong innings to lead the NL East-leading Braves to a 5-3 victory against the San Diego Padres on Friday night.
Keuchel (3-2) held San Diego to one run and six hits, struck out five and walked four in his fifth start since signing as a free agent on June 7. He also started the Braves' final game before the All-Star break, pitching 7 1/3 strong innings in a win against Miami.
"It's just the consistency, reliability," manager Brian Snitker said. "He's one of those guys when he toes rubber, you feel like you're going to win the game. Never any panic, he kind of stays in the moment, goes pitch-to-pitch, hitter-to-hitter, and it's pretty good.
"It's awesome for me. For me, it's the first time I've had one of those," Snitker said. "We've had really good starts, really good pitchers, but he's got a track record. Everybody else is developing their track record."
Keuchel has gone at least seven innings in each of his last three starts.
"It shows my stamina is there, so that's really the main key," Keuchel said. "Even going up to hit a couple times a game, really takes a lot out of you, even though I struck out twice with some heaters. Just little things in the course of the game that I wasn't used to, I didn't know what to expect, coming over to the National League again, but I feel like I'm there. I'd like to push into the eighth or ninth innings one of these next couple of outings. Obviously I've got to do well enough to get there, but I'd like to finish a game here pretty soon."
Padres manager Andy Green said Keuchel did a good job of "avoiding barrels and keeping the ball out of the air. We hit some balls hard throughout the day. I think we scorched some double-play balls today. .. We just didn't come through with that big hit at any point."
Donaldson hit his 19th and 20th homers. It was his 18th career multihomer game and second this season.
Donaldson and Acuna hit impressive home runs off Dinelson Lamet (0-2), who was pitching at home for the first time since the 2017 season. He missed all of 2018 after undergoing Tommy John surgery and returned on July 4, when he pitched well in a loss at the Los Angeles Dodgers.
Acuna, the NL Rookie of the Year in 2018, led off the fifth with an impressive shot to left-center, his 22nd.
Donaldson connected again off reliever Matt Strahm with two outs in the eighth.
"We've seen him earlier. When he gets hot, he's that kind of guy who can carry you," Snitker said.
Donaldson was the AL MVP with Toronto in 2015, the same year Keuchel won the AL Cy Young Award with Houston.
"It's nice. I feel we played a really good game overall," Donaldson said. "Keuchel set the tone, did a great job. I was fortunate enough to put a couple good swings on some pitches and put them out of the park."
Lamet allowed four runs and five hits in five innings, struck out seven and walked two.
"I felt good overall despite how the game turned out," he said through a translator. "That's what gives me some sort of hope, some confidence knowing it's two starts back and the more hitters I'm seeing, the more comfortable I'm going to get.
"I'm trying to execute pitches and when I don't execute pitches and they make contact on the ones that I miss on, that's what makes me mad."
Home plate umpire Dana DeMuth left the game after being hit on the left arm by a foul ball by Freddie Freeman in the first inning. After an 11-minute delay, Angel Hernandez moved from first base to behind the plate and the game continued with a three-man crew.
Padres reliever Andres Munoz made his MLB debut with an impressive scoreless sixth in which he was above 100 mph with several pitches, including one clocked at 101.9 mph. He walked Nick Markakis before getting Austin Riley to ground into a double play and then struck out Brian McCann.
Braves: RHP Julio Teheran (5-6, 3.75) is scheduled to start
Padres: LHP Joey Lucchesi (7-4, 3.94) is scheduled to make his 18th start.
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