Former Knicks center Enes Kanter does a promotion for the...

Former Knicks center Enes Kanter does a promotion for the Portland Trail Blazers' social media department after practicing for the first time with the team Wednesday at Barclays Center. Portland plays the Nets Thursday night. Credit: Brian Heyman / Newsday

He wore the same No. 00 as he did with his old team, but now Enes Kanter had “BLAZERS” emblazoned in red across the front of his black jersey at his first practice with his new team.

“It’s like a first day of school,” Kanter said Wednesday at Barclays Center. “I was actually nervous.”

Kanter was frustrated with the Knicks. They diminished his role because they were developing younger players and basically turned him into an $18.6 million spectator near the end. They failed to trade the 6-11 eighth-year pro and his expiring contract before the Feb. 7 deadline and waived him that day.

Portland signed him six days later to be its backup center, but he didn’t join the team until it arrived in New York Tuesday, following the All-Star break. The Trail Blazers face the Nets at Barclays Thursday night. Kanter arrived with no hard feelings toward the Knicks.

“Oh no, of course not,” Kanter said. “They gave me so much. From day one, not just the organization or players, the whole state just opened their arms, gave me a warm welcome. So I’m definitely thankful for everything, the whole organization, GM [Scott Perry], president [Steve Mills]. I know in the future they’re going to do very well in the East.”

Kanter averaged a double-double (14.0 points, 10.5 rebounds) for the Knicks, who are 11-47. But he sat for six of his final eight games in this second season with them. Knicks fans chanted for him to play.

“Knicks fans, I would just say thank you for being patient with the team, with me,” Kanter said.

“Before I left, I had a conversation with Steve Mills, Scott Perry and David Fizdale,” he added. “It actually went very well. I wished them well. They wished me well. They said there were no hard feelings. I told them, ‘I understand what you guys are trying to do.’ ”

Asked if he would recommend the Knicks for Kevin Durant, Kyrie Irving or any big free agent this summer, Kanter said, “Of course. It’s a very good organization. Good people … Amazing city. So I think that they have a really good chance to get good superstars.”

Back in 2015, Portland signed Kanter to a four-year, $70 million offer sheet. But Oklahoma City matched it. Then the Trail Blazers (34-23, fourth in the West) offered this second chance for the rest of the season. He chose them over playing with LeBron James and the Lakers (28-29).

“It would’ve been very weird coming back to MSG and play against the Knicks,” Kanter said. “But I’m glad I picked Portland. It’s going to be very fun.”

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