Yes, we still have one more day of regular season baseball to play. Sunday’s results couldn’t settle the National League wild-card race, so the New York Mets jumped on a plane to Atlanta for a doubleheader against the Atlanta Braves on Monday (1 p.m. ET on ESPN2). The Arizona Diamondbacks will be watching – they need one of these teams to pull off a sweep to get into the playoffs themselves.

Let’s break down some of the biggest questions from the doubleheader:

Okay, why are we even here?

These are makeup plays from the two Hurricane Helene-related rainouts in last week’s Mets-Braves series. Without them, the Braves, Mets and Diamondbacks are in a virtual tie in the current standings for the final two wild card spots, forcing the two games to be played:

Diamondbacks: 89-73
Mets: 88-72
Braves: 88-72

The most important thing to know here: Both the Mets and Braves have the tiebreaker over the Diamondbacks thanks to winning their season series. That’s why the Diamondbacks need a sweep to get in; if the Mets and Braves split the doubleheader and all three teams finish at 89-73, the Diamondbacks stay home.

Another thing to know: The Braves lead the season series over the Mets 6-5, so a split would leave them as the higher seed.

What are the scenarios for each team to clinch a playoff spot?

Let’s go through these:

1. The Mets win the first game, the Braves win the second game. The Braves are the No. 5 seed and will head to the No. 4 San Diego Padres for a best-of-three wild-card series starting Tuesday. The Mets are the No. 6 seed and will play the No. 3 Milwaukee Brewers. Yes, that means the Mets would have gone from Milwaukee on Sunday to Atlanta on Monday, then back to Milwaukee on Tuesday. (The Braves would have had to fly across the country, but at least they were already in Atlanta.)

2. If the Braves win the first game and the Mets win the second, it’s the same result. The Braves are the No. 5 seed and the Mets are the No. 6 seed.

3. The Mets win both games. New York is the No. 5 seed and will play the Padres. The Diamondbacks are the No. 6 seed and will play the Brewers in a rematch of last year’s wild card series. The Mets travel from Milwaukee to Atlanta to San Diego. (They won’t complain.)

4. The Braves win both games. Atlanta is No. 5 and plays the Padres; the Diamondbacks are the No. 6 seed and will play the Brewers.

Keep in mind that whichever team wins the first game of the doubleheader will clinch a playoff spot. That will provide less incentive – or, actually, No incentive – for that team to play through its best relievers in the second game. Not with the first wildcard game set for Tuesday.

Who are the starting pitchers?

First, remember: the projected starter will likely change for the team that wins the first game.

The Mets will go with right-hander Tylor Megill in the first game. Megill last pitched on September 22 against the Phillies, allowing one run in four innings (but throwing 93 pitches). In the past three starts, he has allowed just two runs. Righthander Luis Severino is scheduled for the second game. His last start was the first game of the Atlanta Series last Tuesday and he took the loss, allowing seven hits and four runs in four innings. He has a 3.17 ERA over his past eight starts.

While the Mets arguably used their top three starters – Sean Manaea, Jose Quintana and David Peterson – against the Brewers this weekend, they are all lefties. These two right-handers might be a better matchup against the right-handed Braves lineup that had a .778 OPS against left-handed pitchers, but .706 against right-handers.

It’s worth noting that if both projected starters are used and the Mets advance — if they lose the first game and win the second — they would have to use Manaea on three days’ rest to start the wild-card series.

The Braves announced that rookie Spencer Schwellenbach will start Game 1. He faced Severino last week and pitched a gem, allowing just three hits and one run over seven innings. He faced the Mets one more time, in July, and had the best game of his career, striking out eleven in seven scoreless innings.

Atlanta’s starter for the second game is – for now – Chris Sale.

Wait, yeah, what’s going on with Sale?

Good question. Sale, who leads the NL in wins, ERA and strikeouts, hasn’t pitched since September 19, when he threw five innings against the Cincinnati Reds. He was scheduled to start one of the rained-out games, but early in the weekend the Braves said they would now save Sale for an “emergency,” i.e., a must-win game. That only comes into play now if they lose the first game.

It’s certainly an interesting strategic decision: if they had won on Sunday with Sale pitching, they would have clinched a playoff spot. Instead, they can use him in the second game if necessary, and if they win the first game, they have Sale ready to start the first game of the wild card series.

Of course there is also this question: is he 100 percent now?

His four-seam fastball averaged 90 mph against the Reds – his lowest average of the season, down from 95.9 mph the start before, and down from his overall season average of 90.8 mph. Maybe it was just a bit of late-season fatigue: He went into four days of rest and his previous start was against the Los Angeles Dodgers, when he had his second-highest average velocity. But a drop of 3 km/h is considered significant, so it’s definitely something to note.

Maybe there’s nothing here. Perhaps the Braves simply held Sale back in the hopes that he wouldn’t be needed and thus would be rested for the start of the postseason. We’ll find out if the Braves lose that first game.

What about the bullpens?

Mets manager Carlos Mendoza used Edwin Diaz to close out the 5-0 win over the Milwaukee Brewers on Sunday. This is understandable; You don’t want to mess around in a situation like that. But it was a safe five-point lead and Diaz ended up throwing 26 pitches. Now there’s a scenario where the Mets need him in six games over five days, including Sunday’s finale, Monday’s doubleheader and the wild-card series.

The Braves are in better shape; none of their top relievers — closer Raisel Iglesias, Joe Jimenez or Pierce Johnson — pitched in Sunday’s 4-2 loss to Kansas City. They also have one of the deepest and best bullpens in the league, so they are in good shape to withstand the rigors of a doubleheader.