LAS VEGAS -- Cody Kessler realizes Southern California could have quit on this season after the Trojans' first head coach was fired.
Or after their second head coach resigned.
Or before their fourth head coach in less than three months took over.
The quarterback and his Trojans simply stuck together, no matter who happened to be in charge. That tenacity got them a blowout win over a BCS contender in the Royal Purple Las Vegas Bowl -- and the confidence that USC is back on the rise after a roller coaster of a season.
Kessler passed for a career-high 344 yards and a bowl-record four touchdowns in the Trojans' 45-20 victory over No. 21 Fresno State on Saturday night under interim coach Clay Helton.
"This is a team that hopefully will be remembered forever in USC history," said Kessler, the game's MVP. "These guys, it doesn't take a lot to get us motivated. When you're playing just for someone else next to you, you don't want to let him down."
Marqise Lee and Nelson Agholor had two touchdown catches apiece, Javorius Allen rushed two more scores, and the Trojans (10-4) answered every question about their motivation by repeatedly dancing on the sideline during the storied program's first postseason victory since 2009.
"I can't say how proud I am of this team," Helton said. "We had to see: Were we going to use it as an excuse to be on our third-string head coach, or were we just going to say, `We're not going to fail today."
From Kessler's smooth offense to a dynamic defensive effort against Fresno State's FBS-best passing game, USC was uniformly outstanding in its only game under Helton.
The offensive coordinator filled the one-game gap between coaches Ed Orgeron and Steve Sarkisian on the Trojans' coaching carousel, but USC picked up right where Orgeron left off after its desultory start to the season under Lane Kiffin. The Trojans ended up celebrating under confetti in the north end zone, joining friends and family on a chilly desert night
"After all of the adversity that's hit us, this win means everything for us," safety Dion Bailey said. "We've had four head coaches and were able to get 10 wins. I'll never forget this team."
Derek Carr passed for just 217 yards and two TDs in his final game at Fresno State (11-2), which fell behind 35-6 at halftime and failed to secure the first 12-win season in school history.
"They had a heck of a run until this point," Fresno State coach Tim DeRuyter said of his Bulldogs. "Physically, they were the most impressive team we've played the last two years. They play inspired."
Kessler outdid Carr, his fellow Bakersfield native and friend, setting the Las Vegas Bowl record for TD passes before halftime and finishing 22 for 30. USC scored three touchdowns in a nine-minute burst in the second quarter, and Allen clinched it with his second TD run with 4:44 to play.
"Blame me. Blame me always," Carr said. "I've got to do a better job of leading, and I've got to do a better job of getting our guys in better spots. That's my fault."
Carr went 30 for 54 under constant pressure from the blitzing Trojans, who eliminated Fresno State's running game and twice stopped the Bulldogs on fourth downs in the first half.
Fresno State's two TD catches by Isaiah Burse and Davante Adams both came on short drives resulting from USC mistakes on special teams, and Derron Smith returned an interception 41 yards for a touchdown.
The Mountain West champions still haven't won a bowl game since 2007, losing six of their last seven.
Lee had seven catches for 118 yards in likely his final game at USC, putting a pleasant finish on a crazy season in Los Angeles.
Kiffin was fired in late September, and Orgeron revived the program with a 6-2 finish to the regular season before resigning in anger when USC hired Sarkisian for the full-time job. Sarkisian watched the bowl game with athletic director Pat Haden in a box above the sellout crowd at Sam Boyd Stadium.
After the teams traded touchdowns on their opening drives, the Trojans blocked Fresno State's extra point attempt -- and it started a deluge.
Agholor caught TD passes of 40 and 17 yards for the Trojans' next two scores. Allen made a 24-yard TD run through bad tackling midway through the second quarter, and Lee turned a short pass into a 40-yard TD with 37 seconds left in the half.