NCAA sanctions that were in effect the previous three seasons included the reduction of 30 scholarships and a roster cap of 75 scholarship players — 10 below the allowable maximum.
The penalties ended last summer, but recruiting classes for all schools are limited to 25 players, so it will take a few seasons for the Trojans to restock the roster and return to 85. USC opened this season with 67 scholarship players.
After nine games, including three defeats, Sarkisian has not wavered. "I've never mentioned it to the team outside of the very first meeting — that 65 vs. 85 will not be a crutch for this football team," he said.
Sarkisian and his coaching staff aside, USC has not shied from publicizing its situation.
The sports information office includes a note about available "recruited scholarship players" before and after every game, numbers that are routinely cited during television broadcasts.
In his most recent "State of Troy" email to season ticket-holders and fans, Athletic Director Pat Haden said: "Given our severely diminished numbers, it is remarkable what we have been able to do with generally less than 50 players each game. It has been astounding."
Has it really?
The Trojans have a record of 6-3 overall, 5-2 in the Pac-12 Conference going into Thursday night's game against California at the Coliseum.
The absence of more scholarship players is most obvious during practices, where some position groups appear short-handed during drills. It also is apparent during games on special teams, where several walk-ons play as first- or second-teamers. Freshman scholarship players who might typically serve as back-ups or be redshirted are playing more significant roles.
Injuries also have taken a toll. A toe issue that has sidelined Tre Madden all season has left the Trojans with only two scholarship tailbacks — Javorius Allen and Justin Davis. That's a far cry from 2007, when the Trojans' went into training camp with 10 tailbacks on scholarship.
But in several instances this season, coaches opted to replace injured players with walk-ons or true freshmen rather than more seasoned scholarship players.
When linebacker Su'a Cravens suffered a knee injury against Washington State, walk-on Matt Lopes played at a nickel spot rather than several available scholarship defensive backs.
Left tackle Chad Wheeler suffered a season-ending knee injury against Utah and was replaced in that game by senior Aundrey Walker, who has 18 career starts. But against Washington State, coaches opted to move freshman Toa Lobendahn from guard to tackle. Walker did not play.
Did lack of depth prevent any one of a number of players from jumping to contest a Hail Mary pass against Arizona State? Or from getting a first down in a critical third- and fourth-down situation at Utah?
Sarkisian has maintained that depth and fatigue are not the issues at the end of games: Mind-set is.
"In my heart of hearts, I think we should be a one-loss football team right now," he said, referring to the Trojans' defeat at Boston College. "We didn't finish a couple games. If we do we're 8-1."
The Trojans have used an average of 51 players each game — three fewer than their opponents. The most was 61 in the opener against Fresno State, the fewest 45 against Stanford. An average of about 43 recruited scholarship players have played each game.
In 2009, the last season before she NCAA imposed sanctions, USC used an average of about 56 players each game, about 49 of them recruited scholarship players. The Trojans finished 9-4 in Pete Carroll's final season as coach.
In 2010, USC was on NCAA probation, but the scholarship-limitation penalty was stayed while the school appealed. The Trojans used about 50 players per game, about 45 of them recruited scholarship players. The Trojans finished 8-5 under first-year Coach Lane Kiffin.
With three regular-season games and a bowl game remaining, Sarkisian's first USC team could finish as well as 11-3 or as poorly as 6-7.
Like Sarkisian, defensive coordinator Justin Wilcox refused to cite depth as an issue. "You're never as deep as you want to be, as a coach," he said.
Several players said the reduced roster had little if any impact.
"I doesn't really affect us too much," junior quarterback Cody Kessler said. "Obviously, when some guys go down it's a little more difficult because we don't have as many guys to replace him.
"But I think our guys have handled it well. Our guys have done a good job of being prepared to play every time."
Junior defensive lineman Antwaun Woods agreed.
"You only can play with 11 people at one time — you don't play 85 at one time," he said.
Sarkisian is looking forward to finishing the season on a high note. The Trojans also appear on their way to building strong recruiting classes for 2015 and 2016.
"We have a chance here to do something really cool at the end of November," he said, "and then we'll be able to assess and address the bigger picture of what our numbers are now, and where we can really improve ourselves moving forward."
Follow Gary Klein on Twitter @latimesklein