ATLANTA — There have been stranger clinching scenarios at the ballpark, but not many.

For the Braves and Mets, Monday’s rain-delayed, playoff-qualifying doubleheader was straightforward, if not simple: Win one of the two games, and advance to the wild-card round of the National League playoffs. Win both, and enjoy the extra bonus of knocking your rival out of the postseason — and help the Arizona Diamondbacks claim the final berth.

In a chaotic, exhilarating, heartbreaking first game of the doubleheader, the Mets rode a six-run eighth inning and a comeback ninth to top the Braves 8-7 and clinch a spot in the 2024 National League playoffs.

Francisco Lindor, who has been battling a back injury, had the game-winning hit, a two-run homer in the ninth.

Atlanta, which carried a 3-0 lead into the eighth and took a 7-6 lead into the ninth, had only minutes to regroup and prepare for the second half of the doubleheader, which is now an all-or-nothing game for the Braves.

The D-backs, meanwhile, can only watch, wait and hope for the sweep.

Braves took early command in game that had unique feel to it

Game 1 wasn’t an elimination game — not for either team involved nor for the D-backs several thousand miles away. No matter what happened in Game 1, there would be a Game 2 starting 30 minutes after the opener’s final out. That meant there was urgency, but not win-or-go-home urgency.

Both teams started slowly, as if working their way upward to playoff intensity. Atlanta sent rookie Spencer Schwellenbach to the mound, and he responded by setting down the first six Mets in order.

In the top of the third, New York’s Tyrone Taylor beat out a bizarre, side-spinning slow roller that cut from 20 feet foul back into fair territory:

Taylor stole second and advanced to third on a sacrifice but was stranded there.

In the bottom half of the third, Atlanta’s Michael Harris II singled up the middle, and Ozzie Albies followed with a 392-foot home run off Mets starter Tylor Megill to break the scoreless tie and stake the Braves to a 2-0 lead.

The Mets’ first serious threat came in the top of the fifth on back-to-back singles by Pete Alonso and J.D. Martinez. But Schwellenbach shut down the challenge, retiring the next three Mets in order.

Ramón Laureano opened the bottom of the sixth with a home run that barely cleared the left-center-field wall, extending Atlanta’s lead to 3-0. A two-out single by Gio Urshela meant the end of the afternoon for Megill. Reliever Huascar Brazobán coaxed a lineout out of Harris and shut down the Braves’ threat, leaving two men on base.

Epic 8th inning for Mets, Braves

Then the Mets finally woke up. Taylor ended Schwellenbach’s day in the top of the eighth, doubling to start the inning. That brought Atlanta manager Brian Snitker to the mound, and Schwellenbach left to a standing ovation from the Atlanta fans. On his second pitch, reliever Joe Jiménez gave up a double to Francisco Alvarez that scored Taylor. Starling Marte followed with a single to put runners on the corners — and the tying run at first — with no one out. Lindor then singled to score Alvarez, cut Atlanta’s lead to 3-2 and chase Jiménez without his even recording an out.

New Atlanta pitcher Raisel Iglesias didn’t fare any better, allowing a single to Jose Iglesias that tied the game. Mark Vientos flew out to center, scoring Lindor to give New York its first lead of the day at 4-3. Brandon Nimmo then thundered a 405-foot homer to deep right to double up the Braves 6-3 and effectively silence most of the Truist Park crowd.

The Braves mounted a massive comeback in the bottom of the eighth, putting runners at the corners with one out. Pinch-hitter Jarred Kelenic then beat out a deep grounder to first base, cutting the Mets’ lead to 6-4. Mets reliever Edwin Díaz loaded the bases, and Albies — who already had that two-run homer in the third — doubled off the top of the left-field wall to clear the bases and give Atlanta the lead again.

The Braves fans’ delirium was short-lived. Atlanta sent Pierce Johnson to the mound to close out the Mets in the ninth. Marte sliced a two-strike single into left, and then Lindor belted a 413-foot homer to right-center to reclaim the lead at 8-7. Atlanta couldn’t respond in the bottom of the ninth … and the first playoff berth went to New York.

The victory takes the pressure off the Mets and puts a crushing, zero-margin burden on the shoulders of the Braves — as well as the Diamondbacks, who must sweat in Arizona and pray for a Game 2 victory by the Mets that would give the D-backs the sixth and final NL playoff berth.

Braves ace Chris Sale was the projected starter for Game 2, but he was scratched due to back spasms. Grant Holmes took the hill as Atlanta’s starter in an elimination game.

Although the Mets are in the playoffs, New York’s exact path remains uncertain as of the end of Game 1. A victory in Game 2, and the Mets would nab the No. 5 seed and face San Diego; a loss and they’d be the 6-seed and face Milwaukee. Atlanta, meanwhile, must play Game 2 at elimination effort, wondering what could have been.

Now, the 2024 season’s final playoff spot comes down to the final game. As it should.