“He said, 'Let's go through this book, but I want this back. I put a lot of work into it. I don’t want this out there for everybody.' I just laughed. I thought it was awesome," Riley said. "His detail of technique is what I love. It’s what I love about football coaching — guys who know the craft and can teach it and is always thinking of good ways to do it.”

Yes, there were questions. Most notably, Parrella has neither coached nor recruited at the FBS level.

"But I'm telling you, when he was done with the interview, I wasn’t concerned," Riley said. "This guy will recruit. He will grab guys. He’s knowledgeable. He’s a magnet. A really neat guy. Passionate. A guy like that, a defensive tackle, does not survive in the NFL for 12 years without something special about him.

“That’s what I admire about those old pros. Some of those guys, when they’re done playing, they don’t know what to do with that passion. He did.”

Riley coached Parrella and kept track of him after his NFL days. He noticed when Parrella took the job at Northern Michigan, right up near the Canadian border.

“I thought, ‘Man, what does Leigh, his wife, think about this?’ I thought, 'Man, does this guy really want to coach.'"