In fact, Mattison is perfectly OK with his switch from defensive coordinator to coaching the defensive line this spring on Jim Harbaugh's staff.
"Whenever there is change over, the coach will hire whoever he wants to hire," Mattison said on Harbaugh retaining him on his staff. "I feel very fortunate to stay at Michigan. I love Michigan. I feel very strongly about the players coming back, the guys in this program, and I feel very strongly about Coach Harbaugh. I have known that family for a long time.
"It's just great to be back. That's the thing I'll say."
Indeed Mattison is glad to be back, considering he did have options elsewhere - including the NFL.
"Well, I had a number of offers," Mattison said. "Some in the NFL and things like that. But I made up my mind that if I had the opportunity I would love to stay. So I stayed."
Michigan plays its annual spring game on April 4.
For more on Mattison, please watch the video provided below.