Complex sentence: Tepper was named the head coach at the University of Illinois in the 1991 season, promoted from defensive coordinator to succeed John Mackovic after Mackovic left to take the head coaching position at the University of Texas.
Split into simpler sentences: Tepper was named the head coach at the University of Illinois in the 1991 season. Hired by John Mackovic as defensive coordinator in 1988, Tepper was promoted to head coach to succeed Mackovic when Mackovic accepted the head coaching position at the University of Texas.