ATLANTA — The margin for error is razor-thin when two of the top teams in the National League square off.

On Thursday night, the Mets came out on the wrong side of those close calls on the way to a 3-2 loss, dropping their first series against an NL East opponent this season at Truist Park.

They had won or tied each of their first 16 division series of the season — tied for the second-longest streak in major-league history since the MLB implemented divisions in 1969.

"We’ve won four when we were back at our place. They won three when we were here," Brandon Nimmo said. "I’m not that disappointed. I’m just more disappointed in I feel like there were some things in this game that we could’ve slightly done a little bit better.

"Maybe we pull away with this one, but that’s baseball. When good baseball happens, it’s usually one or two things."

In a matchup of aces with the Mets' Jacob deGrom and Braves' Max Fried on the mound, both teams did enough to carry a 2-2 tie into the final three innings.

But the Braves got the edge on one split-second play down the stretch.

In the bottom of the seventh, Vaughn Grissom singled and then went in motion on a full count with two outs. Michael Harris knocked a single up the middle and Grissom beat a relay throw from Nimmo to Darin Ruf home to score the go-ahead run.

Francisco Lindor knocked a leadoff single off Braves closer Kenley Jansen in the top of the ninth, but his effort was erased on a hit-and-run attempt. Pete Alonso knocked a towering pop-up dropped between three Braves players and Lindor was thrown out at second base as he attempted to hurry back to first assuming the ball would be caught.

Jansen made the final two outs to help the Braves slice the Mets' NL East advantage to 3.5 games. Now, the Mets head into a difficult test of playing four games in less than 48 hours against the Phillies.

"We’re on to our next challenge," Buck Showalter said. "The first two games were tough. We lost a couple of pitchers. We outscored them yesterday and lost a close one today with a lot of close plays and some things that didn’t quite go our way and some things that they earned."

DeGrom has earned sky-high expectations through his dominance over his career.

More often than not, he lives up to the hype.

In his first start back after more than a year away on Aug. 2, deGrom only allowed one earned run on three hits with six strikeouts. Then, he carried a perfect game into the sixth inning against the Braves on Aug. 7 and followed it up with six shutout innings and 10 strikeouts against the Phillies on Aug. 13.

On Thursday night, deGrom had to shake off some hard contact but he was still able to turn in his deepest start of the season in his fourth outing. The Mets ace worked into the seventh inning for the first time, throwing a season-high 95 pitches but ended up being saddled with the loss.

The Braves tagged him for two runs on three hits in the third inning, including an RBI double from Dansby Swanson and RBI single up the middle from Austin Riley.

"I felt like in the first (the slider) was pretty good and then it really comes down to two pitches — the one to Dansby was just a bad slider over the middle and then the one to Riley," deGrom said. "Those are two mistakes that I wish I had back, but they capitalized on it. It’s frustrating, but it is what it is."

DeGrom sent down 12 straight batters between the third and seventh innings and racked up nine strikeouts in the game, but an infield single that bounced off the glove of a sliding Brett Baty set up the go-ahead run.

"(DeGrom) bent a little bit there," Showalter said. "Gosh, at the level he pitches at, people expect perfection every time he cocks his arm. He was close to it, we just didn’t score any runs."

Taijuan Walker called it some of the worst pain he has felt in his life.

In the bottom of the second inning during Tuesday's loss to the Braves, Walker had to reach down to field a throw from Pete Alonso before he stood up and his back locked up. Walker came out of the game and was diagnosed with a bulging disc in his back.

Walker's injury came on the same day that Carlos Carrasco was placed on the 10-day injured list with a low-grade oblique strain. While Carrasco will miss at least two starts, Walker's status was a little more uncertain.

"Where I’m at today, I feel really good today, which is surprising a little bit myself to where I was Tuesday," Walker said. "We’re not ruling anything out, but we’re just taking it day by day."

Showalter was unsure who would fill in Walker's role if he was unable to pitch. Saturday's probable starters, David Peterson and Trevor Williams, traveled to Philadelphia on Thursday, along with Chris Bassitt. Jose Butto, who is an option for Sunday, was pulled after one inning for Class AAA Syracuse on Thursday. Tommy Hunter is also eligible to return from the IL on Sunday.

Walker said he will not pitch unless he's 100 percent.

"I don’t want to go out there at 90 percent and make it worse and then I’m on the IL and I’m missing two, three, four weeks," Walker said. "I think it’s important that I listen to my body and I think down the stretch the playoffs is kind of where I’m most needed."

After the Mets teared off 31 runs across five games to win four out of five over the Braves at Citi Field in the first week of August, the Braves' starters got vengeance when they returned home.

Fried, who was dealt the loss after giving up six hits and four runs — two earned — on Aug. 6, responded and held the Mets to just two earned runs on four hits on Thursday. The key sequence came as Mark Canha doubled and Brett Baty singled to lead off the third, but Fried got back-to-back strikeouts and a ground ball from Starling Marte.

Canha had four doubles in the series and plated the game's lone runs on a two-run home run in the fifth inning.

"I think you’re seeing a little bit of playoff baseball there," Nimmo said. "That’s the way playoff baseball goes. Every pitch matters. Everybody has their A game on. Fried did a great job tonight of kinda going against his whole game plan from the past two starts, and he executed really well which is hard to do, to be honest, to go to a different arsenal and execute it well."

Fried was not the only one that responded in the series. Spencer Strider only allowed one earned run across five innings with four strikeouts on Monday after only lasting 2⅔ innings and giving up four earned in a loss on Aug. 7. Charlie Morton, who had been tagged for four earned runs by the Mets on May 3, threw 6⅔ scoreless innings with a season-high 12 strikeouts on Tuesday.

It will be back to the drawing board for Mets hitters when they face the Braves' strong staff in the penultimate series in October.

Baty is giving Mets fans plenty of reason for optimism about his future at the hot corner after two games against the rival Braves.

After Canha knocked a leadoff double in the third inning, Baty worked a 2-0 count against Fried and then shot a 104.2 mph single up the middle for the second hit of his major-league career. While a run did not score in the frame, Baty showcased his bat speed to square up the 96.7 mph fastball from Fried.

He's 2-for-7 with a home run, two RBI and a run through his first two games.

But Baty's play that drew the most attention came behind third base. With two outs in the bottom of the fifth, Ronald Acuna Jr. knocked a ground ball down the third-base line that Baty back-handed and threw on a one-hop to first for the final out of the frame.

"You always want a young player to get off well offensively because it’s somewhat of a challenge," Showalter said. "It doesn’t seem like a whole lot with him so far. You also want to see him get off well defensively. He’s done that. He’s made a couple of really good plays there."

Baty made two more outs but could not make a sliding stop on Grissom in the bottom of the seventh. Showalter said he was simply glad that he was able to range to his left to stop the ball from reaching the outfield.