ATLANTA -- What better way to fill the National League¡¯s final two Wild Card spots than by having division rivals square off in a season-ending doubleheader?

The Mets and Braves both entered today's doubleheader needing just one win to secure one of the two available Wild Card entries. The Mets clinched a berth with a stirring come-from-behind win in the opener of the twin bill, but the nightcap will determine who takes the sixth and final spot in the NL as well as which entrant will earn which seed.

What¡¯s at stake?

If the Braves win Game 2, they'll clinch the No. 5 seed and will open their NL Wild Card Series against the Padres in San Diego on Saturday night. If instead the Mets sweep the twin bill, they would take the No. 5 seed, the D-backs would claim the No. 6 seed and the Braves would be eliminated.

This doubleheader was necessitated when inclement weather forced the postponement of the final two games of the Mets-Braves series in Atlanta last week.

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When are the games and how can I watch?

The second game of the single-admission doubleheader is underway and is being televised nationally on ESPN2, while SNY and Bally Sports South are providing local feeds.

What happened when these two teams have met?

The season series between these two teams is tied at six games apiece.

Why does winning the head-to-head season series matter?

When MLB expanded the postseason to its current format in 2022, it also eliminated Game 163 tiebreakers. As such, holding a head-to-head tiebreaker can make the difference between playing into October and falling one game short.

How do the rotations line up for this doubleheader?

The Mets started Tylor Megill for Game 1, and while they were expected to strategically deploy one of their best pitchers, Luis Severino, in Game 2 if Atlanta won the opener, the Mets will instead save Severino for the Wild Card Series.

The Braves turned to Spencer Schwellenbach in the first game and were expected to start ace Chris Sale in Game 2, but Sale was scratched shortly before Game 2 began due to back spasms. Grant Holmes earned the Game 2 nod instead.

What¡¯s the recent history between these two teams at Truist Park?

Back in April, the Mets won two of three in Atlanta, and before Monday's twin bill, they lost last Tuesday's game.

Of course, the most relevant narrative arc points to September 2022, when the Mets entered Truist Park needing only one win to effectively clinch the NL East. Instead, the Braves swept them in a three-game series to retake control of the division and send the Mets spiraling.

This time, each team needs to win only one game.

Are there any injuries of note?

Mets shortstop Francisco Lindor struggled a bit upon returning from a lower-back injury that sidelined him for much of September, but he busted out with a big game on Sunday, going 2-for-4 with a home run, a walk, two RBIs, two runs scored and two stolen bases. He played the entirety of Game 1 at shortstop, hitting a clutch lead-changing homer in the ninth.

Catcher Francisco Alvarez had a tough weekend, exiting Friday¡¯s game in Milwaukee due to back spasms and leaving early on Sunday because of a right hamstring cramp. But Alvarez, who started Game 1 of the doubleheader, came through with a key double during the Mets¡¯ eighth-inning rally in the twin bill opener.

Finally, starting pitcher Kodai Senga has missed all but one game this season due to shoulder, triceps and calf injuries. The Mets had initially hoped he might return for the final week of the regular season, but that won't happen.

Braves second baseman Ozzie Albies was sidelined by a left wrist fracture for two months and is exclusively batting right-handed because he still feels discomfort when swinging from the left side. He had a double, homer and five RBIs in the first game of the doubleheader.

Braves third baseman Austin Riley¡¯s hope to return at some point this year ended when a recent CT scan showed his fractured right hand hasn¡¯t healed enough for him to have the cast removed.