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

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

OK, why are we even here?

These are catch-up games from the two rainouts related to Hurricane Helene in last week’s Mets-Braves series. Without them, the Braves, Mets and Diamondbacks are in a virtual tie for the last two wild card spots in the current table, so the two games have to be played:

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

The important thing to know here: Both the Mets and Braves hold the tiebreaker over the Diamondbacks by virtue of 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 89-73, the Diamondbacks will stay home.

Another thing to know: The Braves lead the season series over the Mets 6-5, so if they split, they would still have the higher seed.

What scenarios are there for each team to secure 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 face the No. 4 seed San Diego Padres in 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 flown from Milwaukee on Sunday to Atlanta on Monday and then back to Milwaukee on Tuesday. (The Braves would have to fly cross-country, but at least they were already in Atlanta.)

2. If the Braves win the first game and the Mets win the second, the result is the same. The Braves are No. 5 and the Mets are No. 6.

3. The Mets win both games. New York is No. 5 and plays 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. (You won’t complain.)

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

Remember, any team that wins the first game of the doubleheader will secure a spot in the playoffs. That will offer fewer incentives – or rather: NO Incentive – for this team to use their best substitutes in the second game. Not with the first wild card game on Tuesday.

Who are the starting pitchers?

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

The Mets are using right-hander Tylor Megill in the first game. Megill last pitched on September 22 against the Phillies, allowing one run in four innings (but threw 93 pitches). He has allowed just two runs in his last three starts. Right-hander Luis Severino is on the schedule for the second game. His last start was Game 1 of the Atlanta Series last Tuesday, and he suffered the loss by allowing seven hits and four runs in four innings. He has a 3.17 ERA in his last eight starts.

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

It’s worth noting here that if both scheduled 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 of rest to start the wild card series.

The Braves announced that rookie Spencer Schwanzenbach 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 again in July and had the best game of his career, striking out 11 in seven scoreless innings.

Atlanta’s starter for Game 2 – for now – is Chris Sale.

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

Good question. Sale, who leads the NL in wins, ERA and strikeouts, has not pitched since Sept. 19, when he went five innings against the Cincinnati Reds. He was scheduled to start in one of the rained-out games, but earlier in the weekend the Braves said they were now saving Sale for an “emergency situation” — meaning a must-win game. This 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 secured a playoff spot. Instead, they can use him in the second game if necessary, and if they win the first game, Sale will be available to them to start the first game of the Wild Card Series.

Of course, the question also arises: Is it now at 100 percent?

His four-seam fastball averaged 92.7 mph against the Reds – his lowest average of the season, less than 95.9 mph the start before and less than his overall season average of 94.8 mph . Maybe it was just a little season-ending fatigue: He started on four days’ rest and his previous start was against the Los Angeles Dodgers, when he had his second-highest average velocity. However, a drop of 2 miles per hour is considered significant and is definitely worth paying attention to.

Maybe there’s nothing here. Perhaps the Braves were just holding Sale back in 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 Game 1.

What about the bullpens?

Mets manager Carlos Mendoza capitalized on Edwin Diaz to cap Sunday’s 5-0 victory over the Milwaukee Brewers. That’s understandable – you don’t want to mess around in this situation. But it was a comfortable five-run lead and Diaz ended up throwing 26 pitches. Now there’s a scenario in which 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 best substitutes – closer Raisel Iglesias, Joe Jimenez or Pierce Johnson – were used in Sunday’s 4-2 loss to Kansas City. They also have one of the deepest and best bullpens in the league, putting them in good shape to withstand the rigors of a doubleheader.