He never stood a chance.

A bouncer who was mistakenly attacked from behind by a woman from upstate New York who thought he grabbed her butt was knocked unconscious almost immediately, video obtained by The Post shows.

Surveillance video from inside Five1Eight nightclub in Plattsburgh shows Kierah LaGrave, 22, putting the bouncer in a chokehold and forcefully yanking his neck from behind. The man’s arms then remain at his side until he’s taken to the ground by the 125-pound pugilist who is now facing a felony charge of second-degree strangulation.

LaGrave coolly gets up after taking down the bouncer, who appears to regain consciousness seconds later before someone comes over to check him out, video shows.

Other footage from inside the club — where LaGrave also works — shows her talking with a friend near the bar before she turns around to dance with her backside facing toward the woman, who is clearly seen playfully slapping LaGrave’s rear. But LaGrave immediately turns around and has her sights set on the bouncer who was simply in the wrong place at the wrong time.

LaGrave, of Plattsburgh, later admitted to police that she choked the bouncer, telling investigators she did so because he had grabbed her. Surveillance footage, however, proved otherwise.

LaGrave has been released on her own recognizance and is expected back in court on Nov. 20, the Press-Republican reports.