Kyle O’Quinn explains why it was so hard to leave Knicks

Kyle O'Quinn NBAE/Getty ImagesThe Knicks have moved on with Noah Vonleh becoming a reliable defensive big man, but coach David Fizdale wanted center Kyle O’Quinn back as “a mentor.’’

Part of O’Quinn wanted to be back, too. In July, O’Quinn, a Queens product, left the Knicks to sign a one-year, $4.45 million deal with the Pacers after opting out of his contract. It wasn’t an easy choice.

“You talk to your agent, talk to people who help you, but you have to make it,’’ O’Quinn said. “It’s the biggest decision I’ve ever made as far as making a choice in my career. I slept on it, prayed on it. I made the decision and I’m sticking with it. It’s no secret I would’ve loved to play for Fizdale or be…