Who are up-and-coming coaches?

Mike Tomlin was once an up-and-coming assistant coach with the Tampa Bay Buccaneers and Minnesota Vikings.

John Harbaugh was once a special teams coach and defensive backs coach of the Philadelphia Eagles.

Cincinnati Bengals head Marvin Lewis led one of the best defenses ever as a defensive coordinator of the Ravens, and Pat Shurmur was a former offensive coordinator of the St. Louis Rams before leading the Cleveland Browns.

So who are the next up-and-coming assistants in the NFL? That is our next topic next week in ESPN.com's Power Rankings.

Are there any future head coaches in the AFC North? Share your thoughts on great assistant coaches in the comment section below. ESPN.com will provide its full list on Tuesday.