Change is coming to Flushing, and not just the type that every team promises at the end of a disappointing season. Real, substantive change should occur soon, with Steve Cohen in possession of a signed agreement to purchase the Mets. Assuming that transaction goes through, the Mets will have a new owner next year. They could also have a new general manager. They will certainly have a roster full of new players.

So when the Mets lost a 15-5 game to the Nationals on Sunday to finish tied for last place in the National League East, they took a renewed sense of optimism with them into the offseason.

• Box score

“I don’t know too much about owning a team, but I just think it’s good for both sides,” outfielder Brandon Nimmo said. “The Wilpons were looking to sell and Cohen was looking to buy, and he’s been a lifelong Mets fan. So I’m glad that someone who’s been a lifelong Mets fan ended up getting the team.”

That much is not yet official, and even if Cohen does complete his purchase in the coming weeks, it isn’t clear how he will operate -- specifically, who might stay and who might go. All the Mets understood for sure on Sunday were their regrets following a challenging, disappointing season that began with playoff aspirations.

• Rojas 'confident' in returning for 2021

Those officially came crashing down when the Nationals swept the Mets in a Saturday doubleheader to mathematically eliminate them. Realistically, fate seemed sealed some days before, as New York struggled to win consistently with a patched-up rotation. But multiple Giants and Phillies losses down the stretch meant that the Mets would have made the playoffs if they had won their final three games.

They didn’t. In Sunday’s finale, Seth Lugo allowed six runs and recorded just four outs, livening the debate about whether he should be a starter or a reliever in 2021. An ex-rotation member, Steven Matz, also served up a Trea Turner grand slam in the rout. Mets pitchers walked 11 batters, including two with the bases loaded, and allowed 22 baserunners.

And so New York fell into a season-ending tie with the Nationals for last place, finishing fourth in the standings for the fourth time in five years. The organization has not come close to making the playoffs since last doing so in 2016. Since the Wilpon family gained majority control of the Mets in '02, the team has qualified for the postseason just three times in 19 seasons.

“We didn’t get it done,” manager Luis Rojas said. “We needed to do it, and we didn’t do it. It was definitely all on us.”

In recent weeks, various Mets have had conversations acknowledging that change is near. As a member of the young nucleus of position players, Pete Alonso -- who hit two home runs on Sunday to finish with a team-high 16 -- is likely to return, along with Nimmo, Michael Conforto, Jeff McNeil, J.D. Davis and many others. Pitching is a bigger issue, with only Jacob deGrom and (probably) David Peterson assured rotation spots. Catching is also a concern, given that the Mets don’t have a starting backstop heading into the offseason.

But there is plenty of room for Cohen and his staff to maneuver. Jed Lowrie and his $20 million contract will be gone, as will Yoenis Céspedes, Wilson Ramos, Marcus Stroman, Rick Porcello, Michael Wacha and others. Come Opening Day 2021, New York’s roster figures to look quite a bit different than it did on Sunday, when the Nationals wore out Mets pitching for 15 runs.

“We know how much talent was on this team, and you don’t always get the promise of next year with the same guys,” Nimmo said. “So it’s tough to know that we missed out on this year. But you’ve got to find a little bit of solace in that it was a good group of guys to be around. It was an interesting season to say the least. … We weren’t able to pull it all together.”

The Mets can’t know if the future will be better than the present. But they have reason to believe it can be.

“I don’t like losing,” Davis said. “And you know what? It’s going to make us even more hungrier to go into the 2021 season.”