George Foster had three hits, including a three-run home run and a two-run double, against visiting Atlanta in New York's 15th victory in 17 games.
Howard Johnson hit a two-run homer in the second and had three RBI; Keith Hernandez had two doubles and a single and two RBI.
Terry Leach (1-0), in his third major league start and his first since 1982, was the winner. Leach, a 31-year-old right-hander, pitched six innings and allowed three runs on six hits and two walks.
The Mets, who beat Atlanta, 16-4, Saturday, finished the season series with a 10-2 margin.
After the game, loser Pascual Perez (1-8), whose 6.52 ERA is the highest of any starter in the league, stormed out of the Braves' locker room and said he was returning to Atlanta. The rest of the team headed to Montreal for a series with the Expos, and Manager Eddie Haas said he did not give Perez permission to miss the flight.
"I can't believe he'd jeopardize things after everything we've done for him," General Manager John Mullen said. "Who knows with Pascual? He may be at the park (Montreal). I'm sure he's frustrated because he hasn't been able to get his season going. It's probably all been building up inside him."
Perez last four innings yesterday, giving up seven runs and seven hits.