ATLANTA — About that momentum thing …

Any thought that the Mets’ sweep of the Subway Series last weekend might turn into a bonafide roll died after the first inning here today in a listless, 6-1 loss to the Braves in the opener of a day-night doubleheader.

Ex-Met Tom Glavine, facing his former team for the first time since returning to Atlanta this offseason, put his old mates back in a deep freeze with six mostly masterful innings of three-hit ball.

Once the Mets let slow-starting Glavine off the hook with one run in the first, the 42-year-old left-hander practically applied a sleeper hold to Willie Randolph’s club, retiring the final 17 batters he faced.

“I watched Sunday night and saw they were swinging the bats well,” Glavine said of the Mets’ 11-2 rout of the Yankees. “I was like, oh, great, they’re getting hot just in time for us. You know that sooner or later, those guys are going to get hot.”

Not this afternoon. With Glavine leading the way, Braves pitchers set down 22 Mets in a row after the first inning until Jose Reyes singled with two out in the eighth.

It was in stark contrast to Glavine’s final outing with the Mets in last year’s season finale, when he allowed seven runs to the Marlins in one-third of an inning to put the finishing touches on the season-ending collapse.

It also was much different than the Mets’ two recent showings against the Yankees.

“You don’t win games on momentum,” David Wright said. “We felt great last weekend [while sweeping the Yankees], but that’s not going to give you more hits or make better pitches on Tuesday.”

Mets starter John Maine didn’t get any boost from his teammates taking two in The Bronx. The young right-hander lasted four innings today, giving up four runs on eight hits and three walks, having his four-game winning streak snapped.

The four innings matched the shortest stint of the year for Maine (5-3), who also lasted four frames in a season-opening loss here April 5. It was even more painful for Maine because Glavine had been such a mentor the previous two seasons.

“It was curious to know he was over there in the dugout watching me pitch,” Maine said.

Maine denied it, but Randolph said his starter wore down in the 81-degree afternoon heat and humidity. The first five hitters in the Atlanta lineup probably had more to do with Maine’s downfall, going a combined 9-for-20 with five RBIs.

First baseman Mark Teixeira went 3-for-3, but catcher Brian McCann did the bulk of the damage, going 2-for-4 with three RBIs. After Maine departed, McCann broke open the game with a two-run homer in the seventh off still-flammable reliever Aaron Heilman.

But it was the hitting — or lack thereof — that frustrated the Mets the most. After erupting for 18 runs combined in the wins at Yankee Stadium, the Mets reverted to their meek-hitting ways.

They went 2-for-8 with runners in scoring position, barely showing a pulse against Glavine, who got Moises Alou and Carlos Delgado to line out in succession with the bases loaded in the first.

“When you let quality pitchers off the hook, it can come back to haunt you,” Randolph said.

Glavine haunted the free-swinging Mets after the first with his trademark combination of perfect control, breaking balls and change-ups. Glavine threw 82 pitches before being lifted to rest his sore knee, including a mere six pitches in the sixth inning.

“He was the Tommy Glavine that he had been for us the past few years; in and out, up and down, changing speeds and keeping us off balance,” Wright said. “We had a good game plan, but he executed his pitches. His control is the best I’ve ever seen.”