As he has so many times, Kristaps Porzingis went up for an offensive rebound. He tried to use his massive 7-foot-3 size to simply outreach his opponents. This time, though he crashed to the floor. He got up and walked.

And felt pain.

Pain almost as worrisome as what the Knicks fans at the Garden felt in their gut.

“I don’t know exactly what happened. I just guess I stepped wrong or something and my foot is a little bruised now. It’s not too bad,” said Porzingis, who notched his 16th double-double with 16 points and 12 rebounds. “I’m going to get some treatment and we have great doctors so hopefully I’ll be back on Wednesday.”

But when the rookie exited with 2:40 left in regulation of the Knicks’ 119-113 double overtime win over the Sixers at the Garden Monday, his health, not his numbers were on everyone’s mind. And he assured everyone afterward that worry and animal sacrifice for his well-being were unnecessary. He did not even go for X-rays or additional tests.

“It’s sore, one spot bothering me at the moment. I’m sure I’ll be fine,” Porzingis said, insisting his youth will aid the healing process.

“I didn’t take any X-rays. I’m sure the bones are fine, just I don’t really know what exactly happened. Just I guess the joint a little bit, but it’s not too serious,” said Porzingis, who felt the discomfort on the bottom of his right foot — officially he came out with a “sore right foot,” according to the team.

Porzingis had been listed as questionable for Saturday’s game by Memphis with a sore right shoulder. But he played.

Even after he exited, Porzingis was not done Monday. He was used as a decoy for Carmelo Anthony’s critical, overtime-forcing 3-pointer. Porzingis entered with 13.6 left in regulation and watched as Anthony scored a triple at :03.4.

“He was a little bit better so with that last play, because of his kind of dual threat — being able to shoot the ball and get to the rim — he could move well enough to do that and then make it a different type of switching situation,” coach Derek Fisher said. “Having to switch to Melo and Kris maybe ending up with a smaller guy. As we got into the overtimes, it wasn’t worth the risk at this point in the season.”

Then he was done for the day. It was hard watching, but it was the smart move Porzingis said.

“That’s extremely hard. I always want to be out there on the floor. Especially siting there on the sideline, knowing that I might help the team in those situations,” Porzingis said. “But I’m really proud of the team, I’m proud of everybody made big plays at the end, hit big free throws and even without me we were able to win the game.”