On Sunday, baseball’s regular season ended – except for the Braves and Mets. They will meet on Monday at Truist Park for a do-or-die doubleheader that will determine their postseason fates.

The Braves could’ve clinched a postseason berth with a win over the Royals on Sunday or a Diamondbacks loss, but Atlanta lost to Kansas City, 4-2, and Arizona beat a San Diego team playing for nothing. In Milwaukee, the Mets won to avoid a sweep.

It sets up a simple scenario: The Braves need to win one of the two games to go to the postseason for the seventh consecutive season. If they are swept by New York, their season ends.

And if the Braves make it, they’ll play in San Diego beginning on Tuesday. This is because for the Braves to earn a postseason berth, they must win one game against the Mets. And if they do that, then they’ll have the tiebreaker over the Mets and will be the No. 5 seed in the National League.

Five observations:

1. In the first game of the doubleheader, the Braves will start Spencer Schwellenbach. If they lose that game, they will throw Chris Sale with their season on the line.

“That’s about as good as I can feel, with Schwelly going the first one and Sale (in game) two,” Braves manager Brian Snitker said. “You know what, the ball’s in our court. If we can’t pull one of those off, then it’s just one of them things.”

The Mets will start Tylor Megill in the first game. They’re saving Luis Severino for a potential second contest.

The Diamondbacks are in an unenviable position. They must hope either the Braves or the Mets are swept, which would allow them to sneak into the postseason. If the clubs split on Monday, Arizona goes home.

How we got here: The Diamondbacks went 2-4 against the Giants and Padres and the Mets went 1-3 against the Braves and Brewers. The Braves, meanwhile, went 3-1 against the Mets and Royals, with their only loss coming on Sunday.

“Obviously, we got a chance to make the postseason,” Matt Olson said. “Same as any day, we gotta show up and win tomorrow. Obviously, you want to do it today and take a little easier route tomorrow, but took two out of three against them. Just didn’t get it done today.”

For a couple weeks, it seemed like the Braves and Mets were battling one another for the third and final wild-card spot in the NL. But because Arizona collapsed in this final week, Atlanta and New York will likely both play in October.

The Braves have controlled their own destiny. They still do.

“I’m very grateful for that,” Snitker said. “We said that a week ago: We just had to win. And we’ve done a good job of going out every day and trying to go 1-0. We were coming off a really big high last night and we wanted to get in today, but that’s baseball. That’s the way it is. We’ll start out fresh tomorrow. It’s two of our better guys going.”

2. How likely is it that the Braves are swept and go home?

There’s no precedent for a situation like this. The Braves and the Mets are in a weird spot.

But here’s some context:

In MLB this season, there have been 28 doubleheaders. Among them, there have been 15 splits and 13 sweeps.

The Braves account for three of those splits. The Mets have been swept once and have split once.

By design, many doubleheaders are split. It’s difficult to sweep them because teams aren’t using their best pitchers in both games.

Here’s another reason to believe Monday will be a split: The winner of the first game will clinch a postseason berth, leaving that club with not much incentive to put anything into Game 2.

It’ll be an interesting day.

“This whole thing here has been a little something that I don’t think anybody’s ever experienced,” Snitker said.

“It’s exciting to play for the playoffs,” Michael Harris II said. “We just gotta come out here and win, and handle business.”

3. Charlie Morton’s start on Sunday began like this: Double, single, three-run homer. The Braves trailed, 3-0.

That would do it for the Braves, whose offense no-showed – again. The Braves took two of three from the Royals, but scored seven runs in three games. Atlanta went 1-for-19 with runners in scoring position this weekend.

“Again, we just had a tough time getting a big hit,” Snitker said.

The Braves on Sunday went 1-for-9 with men in scoring position. They had chances to have a champagne celebration.

In the bottom of the ninth inning, down two runs, they put the leadoff man on base for pinch-hitter Travis d’Arnaud. He struck out. Two batters later, the Braves lost.

And in the eighth, Atlanta had men on first and second with one out. Nothing there, either.

The Royals didn’t exactly play crisp baseball this weekend. And they clinched after Friday’s game, so they adjusted accordingly. Their Saturday starter went two innings. On Sunday, they started a guy who won’t be in their wild-card rotation, and he held the Braves to two runs over five innings.

Snitker’s bullpen kept the game within reach. The Braves used four relievers, and they pitched well, but the offense couldn’t take advantage.

The Royals used four different relievers.

“They showed us a lot of different arms and, I guess, kept us on our toes,” Harris said. “We didn’t get to see the same guy for a good amount of time. They did a good job pitching tonight. We didn’t come through in some situations, but we gotta come back tomorrow.”

4. When Morton exited the game with one out in the fifth, the crowd gave him a nice ovation. It wasn’t as loud as the one Max Fried received on Friday. And maybe fans didn’t have Morton’s future in mind, as they did with Fried.

But they cheered Morton, who had allowed four runs.

It could be Morton’s final start at Truist Park – or the final start of his career. Fans gave him the ovation.

“I mean, I don’t know if that’s what that was,” Morton said, unsure of whether fans were doing it specifically to show appreciation for him. “I just remember I’m walking off the field having allowed four runs, I’m getting pulled in the fifth inning, in a game that means a lot to everybody here. The fans here have supported me ever since I came back. People have been really kind to me, people have been really supportive. When they see me in public, when they see me at the stadium, people have been very, very kind and supportive. To me and my family, (for) the City of Atlanta to make us feel like we’re at home here, it’s been a really special time here.

“But at the same time, my job’s to go out there and to limit runs. And this was obviously a really important game, and for me to have to do that and walk off the field, it’s like, I don’t really expect people to be very enthusiastic about that – because that’s my job, right? That’s why people come out and they cheer for you. Yeah, you can be a really nice dude and a likable person, but you still have to do your job. But I’ve always appreciated the support here in Atlanta.”

Morton, who was drafted by the Braves and debuted for them in 2008, signed back here ahead of the 2021 season. He helped the Braves win the World Series. He’s been a big part of their run of division titles.

He felt like he let his team down Sunday, but his offense could’ve picked him up.

5. It seems fitting that this season – a strange and weird one full of twists for the Braves – comes down to a situation no one has ever seen. A day after the regular season ended for everyone else, the Braves and Mets will play a doubleheader.

“It wasn’t gonna be easy going down to the end,” Snitker said. “We were gonna have to grind through the whole thing. We’re gonna take it right to the very end – literally. And we’ll see. You know what, we’re gonna play two ballgames and hopefully go out there and get some big hits and all that, and make it happen. It’s in our court. It’s up to us to go out and make it happen.”

“Sometimes you just gotta embrace it, you know?” Olson said.

The Braves will throw Schwellenbach and Sale. If they lose with those two on the mound, then, well, it wasn’t meant to be this season.

Schwellenbach has held the Mets to one run over 14 innings this season.

Sale gave up two earned runs over 7 1/3 innings in his lone start versus the Mets this season.

“We feel good about all of our guys on the mound, but Schwelly and Sale have thrown the ball really well as of late – shoot, all year,” Olson said. “So, we feel confident with them throwing the rubber. It’s our job to push a few across for them.”

Stat to know

11-57 - The Braves are 11-57 when they allow four or more runs.

Quotable

“They know what’s at stake. They know what we’re looking at. They’ve been fighting through this all year, the adversity. Just like everybody. Everybody in the game does. That’s what we do. These guys, they’ll be ready and we’re gonna give it our best shot.”-Snitker on how handling adversity this season will help the team Monday

Up next

The first game of Monday’s doubleheader begins at 1:10 p.m. In addition to Bally Sports South and Southeast airing the games, the doubleheader will also be on ESPN2.