The only question was whether it would land fair, but Todd Frazier crushed this fastball so darn hard it never had a chance to hook foul. Home run. Tie game.

And just like that, the close-to-sellout crowd at Citi Field was celebrating in the ninth inning Friday, evoking memories of the Mets’ postseason runs in 2015 and 2016. The ballpark had waited close to three years for this kind of night, and when Michael Conforto’s line drive had cleared Adam Eaton’s head and the winning run had scored, the only thing left was to celebrate the biggest victory of the season.

The ruckus ended with Conforto bare-chested out near second base after Pete Alonso had torn his uniform jersey from his torso and teammates had doused Conforto with water.

Welcome to party central, where official notice was served the Mets are in a playoff race.

“Today was probably the most fun I’ve had up here in the big leagues,” Conforto said after the Mets rallied with four runs in the ninth for a 7-6 victory over the Nationals. “It was special. The stadium was packed. It felt like the playoffs.”

The theme was the same regardless to whom you spoke in the clubhouse after the Mets’ 14th victory in 15 games: Players were energized by the crowd and looking forward to what comes next. Suddenly, the Mets are among the contenders for the National League’s second wild card and are playing like a team that won’t be content unless it storms back to claim the NL East.

Frazier went to the plate against Sean Doolittle in the ninth thinking home run, and got a fastball he could handle. From manager Mickey Callaway’s line of vision in the first-base dugout it was gone all the way, even if most of the ballpark had to wait for a signal. The same fans who had been buzzing after J.D. Davis and Wilson Ramos opened the ninth with a double and single, respectively, against Doolittle were now in full ecstasy.

“There is no doubt about it, we don’t win this game tonight if it isn’t for our fans,” Callaway said. “That was unbelievable and they stuck around. We were down three in the ninth and the stadium was still packed and they were still believing and our players did the job, so that was fantastic.”

Among the foregone conclusions when general manager Brodie Van Wagenen made his “they came and got us” concession speech of sorts last month was that the Mets would be looking for a new manager when this season concluded.

But a funny thing happened on the way to Callaway’s execution: The governor called and said further deliberation was needed.

Lately, it has been Callaway maintaining an even keel and looking every bit like a man reenergized and truly comfortable in the job for the first time since his first few weeks in the Mets dugout in 2018.

Before the Mets opened this big series, I asked Callaway if he felt vindicated by the team’s recent success.

“I don’t think when I look at my job that I am trying to be someone special,” Callaway said. “My only motivating factor is to do something special with a group of guys. None of [the criticism] really bothers me. I come every day and try to do my job to the best of my ability and that is what I hang my hat on at the end of the day.

“Everybody is entitled to their opinion and I understand that at times things have not gone great, and I share in their frustrations during those times, but my job is to be consistent, be a leader and to make sure these guys never quit.”

A few hours later, that persistence was again on display with a ninth-inning rally that may become this year’s version of Asdrubal Cabrera’s walk-off homer against the Phillies in 2016 should the Mets finish this unlikely run and reach the playoffs.

“I was happy,” Alonso said. “I didn’t know what to do, so I ripped [Conforto’s] jersey off.”

There is seldom a dull moment with this bunch.