Kessler, a fifth-year senior, will start for a third season.
He passed for 3,826 yards and 39 touchdowns, with five interceptions, to lead USC to a 9-4 record in 2014.
Kessler’s go-to receiver Nelson Agholor left for the NFL after last season, but JuJu Smith returns. As a freshman, Smith caught 54 passes, five for touchdowns.
Kessler also improved his connection with third-year sophomore Steven Mitchell and sophomore Adoree’ Jackson in spring practice.
Other quarterbacks listed as Heisman candidates include Texas Christian's Trevon Boykin, Ohio State’s Cardale Jones, Clemson’s Deshaun Watson, Auburn’s Jeremy Johnson and Mississippi State’s Dak Prescott.