Barnes hit just his second home run of the season and first since May 3, while also helping starting pitcher Rich Hill turn his night around as the Dodgers erased an early four-run deficit to defeat the New York Mets 11-4 on Tuesday.
David Freese hit his first homer with his new club and the Dodgers remained a half-game behind first-place Colorado in the NL West. The teams meet this weekend for three games at Coors Field.
Barnes was such a revelation for the Dodgers last year that he started 13 postseason games, including all seven in the World Series. But Yasmani Grandal has returned to being the team's primary catcher, while Barnes' bat has slumped. Dodgers pitchers, though, have continually praised Barnes' work behind the plate.
"It was obviously a tremendous swing and he did a great job again tonight behind the dish," Hill said. "He's obviously one of the best catchers in the league and to see him swing the bat the way he did tonight was great."
The Dodgers won for the ninth time in 11 games, while the Mets fell to 4-4 on their nine-game trip to Chicago, San Francisco and Los Angeles.
"You don't have (comfort) against these guys, not in this park, not with the way the roster's constructed," Mets manager Mickey Callaway said. "It's going to be a long game because whoever you bring in, they've got weapons off the bench."
Freese, who made his Dodgers debut Saturday after he was acquired from the Pittsburgh Pirates, pulled Los Angeles within a run in the fourth when he went deep against Mets starter Jason Vargas for his 10th home run.
"It's a great pickup," Dodgers manager Dave Roberts said. "It's a professional at-bat. It's the willingness to do whatever we ask of him. He's a guy that has been in big spots and has performed, so to have him on our roster for depth is huge."
The Dodgers added two more runs in the fourth inning, one on Barnes' grounder to third base that was misplayed by Todd Frazier for an error, and another on a fielder's choice grounder from Brian Dozier that gave Los Angeles a 5-4 lead.
The Dodgers broke open the game with six runs in the seventh. Manny Machado, Freese and Enrique Hernandez all drove in runs, and Machado scored from second base on a wild pitch by reliever Corey Oswalt. Yasmani Grandal capped the outburst with a two-run double.
Los Angeles' comeback resembled the high-power club that swung its way to Game 7 of the World Series last year.
"I think it's starting to turn a little bit," Barnes said. "I think we all know what we are capable of."
Vargas (5-9) gave up six hits and five runs -- four earned -- in 3 1/3 innings. He allowed four earned runs over his previous four starts.
"I think just not being able to get that low call, especially," Vargas said. "I felt there were some pretty good pitches in there that would have set some at-bats up a bit differently, and things just didn't go our way after that."
Hill (7-5) permitted four runs and seven hits in six innings with a walk and eight strikeouts. After Frazier doubled following Conforto's home run, Hill gave up just one more hit until he was removed to start the seventh.
The Mets have dropped 13 of their last 14 regular-season games to the Dodgers going back to May 28, 2016.
Dodgers third baseman Justin Turner received two honors on Tuesday. He was chosen the National League player of the month for August, and selected the team's Roberto Clemente Award nominee for his work on and off the field. Turner returned from the disabled list Aug. 2 and batted .402 in August with 22 runs, 11 doubles, six homers and a 1.213 OPS.
Mets: C Devin Mesoraco was feeling residual soreness after straining his neck and back on a swing Monday, but tests showed he did not have a serious injury. ... Callaway said RHP Anthony Swarzak, on the DL since early August with right shoulder inflammation, could be activated during the team's upcoming seven-game homestand, which begins Friday against Philadelphia.
Dodgers: RHP Kenley Jansen met with a team cardiologist, and the Dodgers are still trying to determine if their closer will travel this weekend to Colorado, where he has twice experienced an irregular heartbeat.
RHP Zack Wheeler (9-7, 3.37 ERA) pitches for the Mets on Wednesday. He is coming off a tough-luck loss at San Francisco on Friday that snapped his seven-game win streak going back to July 14. LHP Hyun-Jin Ryu (4-1, 2.24) will start for the Dodgers. He has a 2.38 ERA in four starts since coming off the disabled list after being sidelined by a left groin strain.
More AP MLB: https://apnews.com/tag/MLB and https://twitter.com/AP-Sports
Mahomes used to big time environment thanks to his dad
Ian O'Connor joins OTL to discuss Patrick Mahomes' time spent with his father while he was a major league pitcher.
Longtime Reds broadcaster Marty Brennaman will retire after 2019
Longtime Cincinnati Reds broadcaster Marty Brennaman will retire after the 2019 season, his 46th with the club.
White Sox make $175 million pitch to Manny Machado
Star shortstop Manny Machado has at least one pitch from the Chicago White Sox, who made a seven-year, $175 million offer, multiple sources told ESPN's Buster Olney.
Buster's Buzz: In changing market, veteran outfielders hit hardest
They used to score big in free agency. Here's why many outfielders are lately being left out in the cold.
Foxworth, Spears get heated about Murray's NFL potential
Domonique Foxworth and Marcus Spears get fired up debating if Kyler Murray should play baseball or football.
Patrick Mahomes inherited clutch gene from his major league dad
Can the Chiefs quarterback remain composed as the postseason stages get bigger? His family history might give him a distinct advantage.