David Wright took off from first base on a line drive by Yoenis Céspedes into right-center field in the opener of a crucial series against the Mets’ closest NL East pursuer. As the ball skipped off the fence and was retrieved by the Washington Nationals’ Bryce Harper, Wright turned at third with the intent of heading home — determined to increase New York’s lead in the seventh inning.

Not long ago, it was unknown if Wright, diagnosed in May with spinal stenosis, would play again this year — or ever.

But here he was, in the middle of a key late-season contest — looking to help the Mets reach the postseason for the first time since he was a rising superstar back in 2006.

The emotion that must have been stored up during his time away from the playing field was evident just after he slid safely ahead of the throw from Anthony Rendon and the tag from catcher Wilson Ramos, as he unleashed a violent fist pump accompanied with a primal scream to provide an image (and a GIF) for the ages.

That thrilling sequence made the score 8-5, an advantage held thanks to a brilliant 4.2 innings of work from the bullpen and made possible by clutch hitting from their recent additions to the lineup.

“What a game,” Wright said afterward. “Just, what a game.”

The importance of this series was heightened as New York came off a stumble in Miami. That, combined with Washington’s five straight victories might have suggested a swing in momentum as the Mets held a four-game division lead.

The sweep of the Nationals just over a month ago proved they were prepared to challenge the once-presumed division champs. So even when Wilson Ramos unloaded a grand slam off starter Jon Niese to punctuate a five-run fourth inning, the Mets were yet again unfazed. The Washington outburst nullified the 3-0 lead New York built on the strength of home runs from rookie Michael Conforto, ex-Brave Kelly Johnson, and former Tiger Céspedes.

But against Max Scherzer, New York responded — first with an RBI double by Curtis Granderson in the fifth followed by a sacrifice fly from Travis d’Arnaud in the sixth. Washington’s ace would be lifted with a no-decision.

Then came the decisive top of the seventh. Wilmer Flores led off with a single and moved over to second on a bunt. Granderson walked and Wright singled to produce the go-ahead run. Daniel Murphy drove in Granderson with a fly out to left field. And, finally, the exclamation point of the Céspedes double and Wright’s emphatic celebration.

While the Mets ambushed Washington’s woeful bullpen, the Nats managed only three hits following Niese’s departure in the fourth. New York had set the tone for this three-game set in D.C. with the best still to come.