Knicks guard Frank Ntilikina during warmups against the Brooklyn Nets...

Knicks guard Frank Ntilikina during warmups against the Brooklyn Nets before a preseason game at Madison Square Garden on Oct. 3, 2017. Credit: Kathleen Malone-Van Dyke

GREENBURGH, N.Y. — The Knicks left for their first road preseason game Thursday without Frank Ntilikina.

The rookie point guard stayed back to rest and get treatment on a contused right knee. Ntilikina suffered the injury in Tuesday’s preseason opener against the Nets when he banged knees with teammate Enes Kanter on a defensive sequence.

Ntilikina said it swelled up, but he doesn’t think it’s anything serious. It’s the same knee that kept him out of the entire summer league, but he said it’s not related to that.

“They told me I was OK, I was OK and that was just a coincidence that happened during the game,” Ntilikina said Thursday. “So we’re going to treat it and hopefully I’ll be back [Sunday].”

Ntilikina was limited by a sore groin earlier in the week, but he still played Tuesday. He needs experience, but the Knicks will continue to be cautious with him.

After Friday’s game at the Wizards, the Knicks play back-to-back games Sunday and Monday against the Nets and Rockets.

“I’m always disappointed to miss a game but I have to do what I can to be ready for this long season,” said Ntilikina, whom the Knicks selected with the eighth pick. “I’m going to stay here and get treatment and hopefully I’ll be back for the next game.”

The Knicks said it was precautionary when Ntilikina missed the summer league because he had just completed a long season playing overseas and in the French League championships.

He flew to New York for the draft, flew back to play in the championship game and then joined the team for summer league in Orlando.

“We saw it on tape. It was a collision,” coach Jeff Hornacek said of Ntilikina’s knee. “From summer it was more wear. He wasn’t in line exactly right. I don’t think it’s related at all.”

The Knicks listed Mindaugas Kuzminskas (sore left calf), Ron Baker (sore left ankle) and Luke Kornet (sore left hamstring) as doubtful for Friday’s game. None of them played Tuesday.

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