PHILADELPHIA — OG Anunoby saved the day — and then almost ruined it — and then saved it again. 

When the Knicks lead had dwindled to three points with just under two minutes left in the game, his putback dunk gave them breathing room. When it went back down to two, he drilled a 3-pointer to put them back up five points. After a stop, he assisted Landry Shamet, who drilled a 3-pointer to put the Knicks up eight. 

But with the Knicks up three with 9.9 seconds left, Anunoby went up for a layup — instead of dribbling the ball out — and was fouled. But the call was reversed after a 76ers challenge, giving Philadelphia the ball with a chance to tie the game. 

Then Tyrese Maxey missed a 3-pointer, and Jalen Brunson was fouled — but promptly missed both free throws, giving the 76ers another chance to tie the game. Then Anunoby stole Joel Embiid’s pass to seal the 112-109 win Saturday afternoon at Xfinity Mobile Arena. 

What a roller coaster. The final ticks of which saw Mikal Bridges (3-for-16 from the field) and Karl-Anthony Towns (just 16 minutes played) on the bench.

“Just pure chaos, but we found a way to win,” Brunson said. “That’s the best way I can describe it.”

The Knicks led by as many as 17 in the fourth quarter before the Sixers slashed the lead all the way down to two. It marks the first back-to-back wins the Knicks have had since late December.

Anunoby spent the end of the game guarding Embiid, as the Knicks went with a small lineup. That’s because Karl-Anthony Towns fouled out during the middle of the quarter. 

But Towns’ latest foul trouble was a blessing in disguise. 

He picked up his fourth foul — second offensive — with 10:24 left in the third quarter. It forced Knicks coach Mike Brown to take him out and put Mitchell Robinson in the game. 

And that’s precisely when the game changed. The Knicks immediately went on a 12-0 run and took control before letting the 76ers back into the game in the final minutes. 

Embiid had looked like his former MVP self, bullying Towns for 28 points in the first half. He only finished with 38 — and did not score in the third quarter, when Robinson was in the game and guarding him. It brought back memories of the first-round playoff series two years ago, when Robinson and Embiid went at it. 

“Playing against him is always gonna be a little fight,” Robinson said. “That’s our nature, it is what it is. … I know he got it going earlier on and he’s an All-Star player so with a guy like that, you’ve gotta come out there and fight and make some adjustments yourself.”

Then Towns was back in the game to start the fourth quarter — and 15 seconds later he picked up his fifth foul. Back to the bench he went, with Ariel Hukporti coming in this time. He was able to hold his own. 

Towns came in one more time with 7:29 left in the game. The 76ers scored six straight points before Towns fouled out two minutes later, giving up an and-1 to Embiid. Robinson re-entered and promptly grabbed an offensive rebound, which led to a Shamet 3-pointer, and then stole the ball from Embiid.

Towns finished with just 10 points. The Knicks were at their best with him on the bench. 

Brunson recorded 14 first-quarter points en route to a team-high 31. But he was uncharacteristically not at his best down the stretch. Anunoby added 23.

“OG changed the game defensively,” Brown said. “And his quick decisions with the basketball. It was beautiful to watch.” 

Brown has repeatedly recognized Miles McBride and Shamet as the Knicks’ best point-of-attack defenders. McBride missed the first of two previous matchups between these two teams, and Shamet missed both — two Knicks losses in which they were overrun by the 76ers’ explosive backcourt of Maxey and VJ Edgecombe. 

But with both back in the fold, the Knicks were able to contain them both. They scored 22 and 14 points, respectively, unable to break down the Knicks defense like they had the previous two meetings. 

The Knicks held a 26-4 advantage in second-chance points. Robinson and Josh Hart, who grabbed six and five offensive rebounds, respectively, were central to that. 

Brown also won two challenges. The second, in particular, was crucial — instead of a foul on Brunson on an inbounds with 33.3 seconds left and the Knicks up three, it was changed to a foul on Edgecombe. Since it was a dead-ball foul, it gave Brunson a free throw and the Knicks possession after the free throw. 

The arena was full of Knicks fans, making it sound like a home game at Madison Square Garden — particularly during the third quarter. 

“We played well, but our execution the last couple minutes, I don’t know if we deserved to win the game,” Hart said. “I don’t know if they deserved to win the game either. So it was just a toss up, we could have just tied, honestly at that point, just all the miscues that we did.” 

After losing nine of 11 games, a rout of the Nets — even in historic fashion — wasn’t going to be proof the Knicks were back on track. 

But a win over the 76ers is more convincing, even if there was a bit of mayhem.