Let me remind you that Butkus played both ways as well in college. He was actually playing Center and linebacker from 1962 through 1964.
Butkus was absolutely amazing in college at the University of Illinois. He was chosen for the 1964 All-America team by five of the six major selectors. In a cover story for Sports Illustrated that season, sportswriter Dan Jenkins remarked, "If every college football team had a linebacker like Dick Butkus of Illinois, all fullbacks soon would be three feet tall and sing soprano." He also finished 6th in the Heisman Trophy balloting in 1963 and third in 1964. This is something rare both for a lineman and a defensive player.
When Butkus saw the list, he reacted by saying: