RJ buries off-glass 3 at buzzer to lift Knicks in thrilling win over Celts

A heave. A prayer. And a thrilling Knicks victory.

RJ Barrett jumped sideways and was falling down as he buried the first game-winner of his Knicks career on Thursday, watching it bounce off the backboard and into the net to finish a comeback 108-105 victory at the buzzer.

On the previous play, Barrett was beaten off the dribble and arrived too late to contest Jayson Tatum’s tying shot for the Celtics. Overtime felt imminent.

But Barrett received the inbounds with 1.5 seconds left and returned the favor by shooting over Tatum, and the Knicks celebrated wildly with each other and fans behind the scorer’s table.

They deserved the moment. The Knicks (19-20) trailed by as many as 25 points Thursday, and required a stupendous shooting performance from Evan Fournier to reach their buzzer-beating climax.

Fournier scored a career-high 41 points while hitting 10 of his 14 three-pointers. His trey with about two minutes remaining provided New York its first lead of the game.

For much of the night, the Knicks looked overmatched. Barrett (just 4-for-15 shooting) struggled until his miracle game-winner. Julius Randle (22 points, 8-for-20 shooting) didn’t come alive until late in the third quarter.

Tatum (36 points), meanwhile, was cooking.

But Fournier kept the Knicks alive, just two nights after going scoreless in a loss to the Raptors. The Frenchman, who played for Boston last season, has struggled mightily since signing his $78 million deal in the summer, but he’s been a monster against the Celtics. He dropped 32 points apiece in the first two matchups versus his former team, and represented a lone Knicks bright spot Thursday until the team’s third-quarter surge.

All three of his 30-point games as a Knick have arrived against the Celtics.

Still, the Knicks trailed by 25 in the second quarter and 20 in the third. It wasn’t until a 16-3 run before the start of the fourth that the home team looked like it might snap a two-game losing streak.

Randle, in particular, regenerated with verve and spirit late in the third quarter, bullying the Celtics in the paint and shouting at the crowd.

A day earlier after practice, Randle was mixing in expletives while explaining why he doesn’t care about the wave of criticism he’s endured this season as the face of the Knicks’ struggles.

“I really don’t give a f--- what anybody has to say, to be honest,” Randle said. “I’m out there playing. Nobody knows the game out there better than I do, compared to what everybody has to say. So I really don’t give a s---. I just go out there and play.”

But Randle certainly looked like he cared in the third quarter Thursday, when the Knicks cut a 20-point deficit to 7 over just about four minutes.

With Nerlens Noel still working his way back from a bout with COVID-19, Mitchell Robinson moved into the starting lineup and scored seven points in 27 minutes, including a game-tying alley-oop with 1:20 remaining.

Immanuel Quickley was also a catalyst off the bench with 16 points in 25 minutes.