Young was a four-time Pro Bowl selection during his 14 years with San Francisco. He will assist defensive coordinator Dan Quinn, who coached Young for four seasons (2001-04) in San Francisco.
Young has limited coaching experience. The former Notre Dame star returned to his alma mater in 2009 and worked as a graduate assistant under Charlie Weis, now Florida's offensive coordinator. Young got his first full-time job last season, serving as defensive line coach at San Jose State.
Muschamp says he wants to build the program on toughness and "there are not too many people tougher than Bryant."