The Kristaps Porzingis blockbuster wasn’t cheered by all, especially not by rookie Kevin Knox.

It was a double whammy for Knox. The Knicks lottery pick saw a bright future with Porzingis as a forward tandem. And in the short term, Knox lost his top mentor, veteran Courtney Lee, who had taken the 19-year-old under his wing.

“He was the guy I talked to all the time for advice,’’ Knox told The Post. “He was the person I talked to if I needed help with anything on the court or off the court. It’s hard to see him go. We talked a lot. He gave me a lot of information.”

It’s been a roller-coaster rookie year for Knox, who is averaging 12.6 points per game but appears to be hitting the rookie wall, although Knox responded with one of his strongest outings of the last two weeks against Toronto on Saturday with 20 points, making 4-of-9 3-pointers.

“[Lee] said to stay in touch, that we’ll work out over the summer, keep working hard and the sky is the limit for what I can do,” Knox said.

Even if Porzingis didn’t travel to road games and never was cleared for practice, Knox said the 7-foot-3 Latvian made an impact on him.

After Knox was taken ninth in last June’s draft, Porzingis Facetimed him that night from Spain — a development president Steve Mills found encouraging. It was fleeting, however.