Sullivan said Wednesday in a statement that he won't be able to make the trip for Saturday's game with TCU because of complications from neck surgery in April. Assistant head coach and defensive coordinator Bill D'Ottavio will lead the team for the opener.
Sullivan was TCU's head coach from 1992-97.
He is a former Auburn quarterback who won the 1971 Heisman Trophy. He has been Samford's head coach since December 2006.
Sullivan says his wife, Jean, and two children ''will be there to support the Bulldogs and reconnect with many of our old TCU friends.''
Samford made the Football Championship Subdivision playoffs last season for the first time since 1992.