It was at this stage last season when the Mets began their epic collapse. They had a seven-game cushion before going 5-12 down the stretch and letting Philadelphia charge past them for the division crown.
Beginning their final 17-game stretch this year, the Mets let the opener slip away but rebounded in the nightcap. They have won 21 of 29 overall.
Jeff Francoeur hit a tying single in the eighth inning of the first game and Atlanta rallied against Johan Santana and the Mets' bullpen, beating New York 3-2 for its first one-run road win in more than a year.
Omar Infante's sacrifice fly put the Braves in front, capping a three-run eighth.
Mike Gonzalez closed out Atlanta's fourth straight win with a perfect ninth and the Braves won a one-run game away from home for the first time since a 7-6 victory on Aug. 9, 2007, also at Shea Stadium.
Atlanta had lost 22 such games in a row this season and 29 overall - the longest streak of its kind in major league history, according to the Elias Sports Bureau.
"We enjoyed it. There was a lot of excitement in that dugout, in that locker room, when you win a game like that," Kelly Johnson said. "Let's make it hard on these guys. Maybe they collapse again."
Niese (1-0) did his best to prevent that.
The 21-year-old lefty, born the day the Mets won the 1986 World Series, allowed six hits and struck out seven after getting roughed up in his debut Sept. 2 at Milwaukee.
Beltran also doubled, singled and scored twice. Wright hit a two-run shot off Jo-Jo Reyes (3-11) in the first and Fernando Tatis polished off the inning with a two-out RBI single.
Niese was tabbed for this start after Friday night's rainout forced the doubleheader. The Mets, missing injured John Maine, pushed back Pedro Martinez until Monday night at Washington, saying they didn't want to start two unproven pitchers in that four-game series.
The club's top pitching prospect, Niese delivered in a big way.
With the scattered crowd chanting "Let's Go Niese!" he got Omar Infante to foul out for the final out of the eighth and pumped his first.
Luis Ayala worked a two-hit ninth, completing New York's 11th shutout. The Braves have been blanked 14 times.
Niese even got his first major league hit, an infield single in the fourth.
After ex-Met Mike Hampton kept the Braves close in the opener, Jeff Ridgway (1-0) worked a scoreless seventh to win his first career decision. Gonzalez earned his 10th save in 11 chances.
Scott Schoeneweis (2-4) took the loss, allowing a single to his only batter.
"Even though we're in first place, it's not over yet," Santana said. "We still have a long way to go. We have to protect our lead. We have to play better baseball. We have to do the little things."
It was New York's second doubleheader in seven days and sixth this season, its most since playing eight in 1998. The Mets are 0-1-5 in twinbills. They were swept May 20 at Atlanta.
In the opener, Santana struggled with his command early but kept Atlanta off the scoreboard and carried a 2-0 lead into the eighth.
Consecutive singles by Brian McCann and Yunel Escobar to start the inning chased Santana, 6-0 in 14 starts since his last loss June 28 against the Yankees. He left to a warm ovation and tipped his cap to the crowd.
Once again, New York's shaky bullpen couldn't hold a lead for the lefty ace. Schoeneweis gave up a single to Casey Kotchman that loaded the bases, and Francoeur grounded Brian Stokes' first pitch through the middle for a two-run single.
Josh Anderson sacrificed, pinch-hitter Greg Norton was intentionally walked and Infante gave Atlanta the lead with a sacrifice fly.
It was the seventh time in 31 starts with the Mets that Santana left with a chance to win only to have the bullpen blow it. Five of those collapses have come in the ninth inning.
"He did his job, did what he was supposed to do. We didn't take advantage of it," manager Jerry Manuel said.
Notes: The Mets are 6-8 against Atlanta this year. ... Nursing a stiff back, Atlanta 3B Chipper Jones missed both games. He hopes to return to the lineup Sunday for his final chance to play at Shea Stadium, one of his favorite ballparks.
