Steve Sarkisian

USC Coach Steve Sarkisian will have 56 players on his spring roster who are under scholarship. (Allen J. Schaben / Los Angeles Times / February 5, 2014)

A new era begins Tuesday at USC.

Steve Sarkisian, who was hired in December, will oversee his first spring workout as the Trojans' coach.

The tumult that marked the 2013 season — the Trojans were playing for their third head coach when they defeated Fresno State in the Las Vegas Bowl, with a fourth (Sarkisian) already hired — has been replaced by optimism as the team prepares for a 2014 schedule that includes home games against Fresno State, Oregon State, Arizona State, Colorado, California and Notre Dame and road games at Stanford, Boston College, Arizona, Utah, Washington State and UCLA.

Absent from the roster are five players who made themselves available for the NFL draft.

Added to the roster are five players who graduated early from high school or transferred from a community college to enroll for the spring semester and participate in spring practice.

The Trojans are in the final season of NCAA sanctions that limit them to a maximum of 75 scholarship players. As Sarkisian prepares for the summer arrival of 14 freshmen, he has 56 scholarship players on the spring roster.

Several players recovering from surgeries will kept out of practices or limited so that they remain on track to be physically sound for training camp.

"We have to be cognizant of the fact that, with our numbers, the amount of reps that we're accustomed to having overall is not going to be the same," Sarkisian said.

The Trojans will have 15 practices, including a scrimmage at the Coliseum on April 19.

Here are the main questions facing the Trojans:

Can Max Browne challenge Cody Kessler for the starting quarterback job?

Kessler, a fourth-year junior, led USC to 10-win season, passed for 20 touchdowns with seven interceptions, and finished with a flourish against Fresno State in the Las Vegas Bowl. He is a seasoned team leader with game experience who was bound to play for Sarkisian at Washington — until USC offered him a scholarship the day he was going to commit to the Huskies.

The 6-foot-5 Browne, a redshirt freshman, has matured physically since arriving at USC in January 2013 and he puts in extra work on and off the field. So it will be no surprise if he displays improved arm strength and presence.

Jalen Greene, an early enrollee from Gardena Serra High, will begin his on-field acclimation to college football.

Having already lost one quarterback — Max Wittek is transferring — it would be no surprise if Sarkisian says in April that competition will continue regardless of how it plays out the next five weeks.

Will George Farmer and Steven Mitchell emerge as receiving threats?

With Marqise Lee's departure, junior Nelson Agholor is the No. 1 receiver. Sophomore Darreus Rogers showed last season that he is probably the most sure-handed pass catcher in the receiving corps.

So all eyes will be on Farmer, a fourth year-junior, and Mitchell, a redshirt freshman, who sat out last season while recovering from knee surgeries.

Junior Victor Blackwell also will be given the opportunity to push for a larger role.

Who will replace Marcus Martin at center?