LOS ANGELES -- In less than two weeks, Southern California went from the depths of a coach's firing to the heights of a wild celebration after beating the No. 3 team in the nation.
Most of these Trojans have been on a roller coaster from the day they joined this storied but troubled program. This particular peak sent them soaring over mighty Utah.
Cameron Smith returned the second of his three interceptions 54 yards for a touchdown, and USC knocked the third-ranked Utes from the unbeaten ranks with a 42-24 victory Saturday night.
Ronald Jones II, Justin Davis and fullback Soma Vainuku rushed for scores to help the Trojans (4-3, 2-2 Pac-12) snap their two-game skid and earn a victory for interim coach Clay Helton in his debut game at the Coliseum.
"These guys want to prove to everybody what type of team they are," Helton said. "When we play together and play like we did tonight, they're a very hard football team to beat. There's a lot of talent in that room."
Cody Kessler passed for 264 yards and a touchdown and rushed for another score, while JuJu Smith-Schuster had eight catches for 143 yards and a fourth-quarter TD that wrapped up the win. The sounds of the Trojans' celebration could be heard through the walls of the Coliseum, where USC had lost its previous two home games.
The Trojans were outstanding in their first appearance at the venerable arena since an embarrassing loss to Washington and the subsequent firing of coach Steve Sarkisian. After Helton took over for last week's narrow loss at Notre Dame, he became the eighth straight USC coach to win his first home game when his Trojans dominated the Pac-12 South leaders.
"It's been tough, and these guys have been pushed to the limit, but (Helton) has kept everything together," Kessler said. "He has kept us family. It was a great win, but that's what we expect."
Smith, USC's dynamic freshman linebacker, led a fine defensive performance by picking off Travis Wilson's throws and making three returns for a combined 122 yards, including his scoring romp down the USC sideline 1:07 before halftime.
"Any time a big play happens, the whole team feels it," Smith said. "We piggyback on each other and make more big plays."
Utah was second in the nation in turnover margin entering the game, forcing 19 turnovers and committing just seven. The Trojans erased that advantage thanks to Smith, the first USC player with three interceptions in a game since Jason Oliver in 1991 against Penn State.
"In my opinion, that's the best team we have played all year long, for certain from a personnel standpoint," said Utah coach Kyle Whittingham, whose Utes have beaten Oregon and Michigan. "Give them credit, they played well. Tough to give them essentially three touchdowns on turnovers and hope to have a chance to win against a team of that caliber."
Britain Covey caught two touchdown passes for the Utes (6-1, 3-1), whose eight-game winning streak ended.
While Wilson threw four interceptions during a rough night for the Orange County native, Utah also inexplicably failed to establish its running game against USC, which had been bullied up front this season. Star tailback Devontae Booker had just 14 carries for 62 yards, and Bubba Poole rushed for a score.
"We didn't expect to get punched in the mouth like that," Utah linebacker Gionni Paul said. "I forgot what it feels like to lose. I'm so used to winning. It's a bad feeling. A lot of guys in the locker room didn't like that, so I don't think we are going to lose anymore."
The tumult-plagued Trojans entered the night as slight betting favorites against the powerful Utes, and USC proved Vegas' prescience with an excellent game plan that largely played to its strengths. Jones and Davis combined for 139 yards rushing, and Smith led an aggressive defensive effort that limited Utah to 213 yards in the first three quarters.
Smith returned his first interception 41 yards to set up Vainuku's fourth-down TD dive. In the second quarter, Smith took his second interception to the house, putting the Trojans up 28-14.
"In practice and spring, he had the best hands on the team," USC safety Chris Hawkins said of Smith. "And then all this season he couldn't catch a thing. We've been taunting him about it this week. I guess he heard."
USC played without injured receivers Steven Mitchell Jr. and Darreus Rogers and three key offensive linemen: center Max Tuerk, left tackle Chad Wheeler and backup center Toa Lobendahn, who was injured in the first half. Utah was without top linebacker Jared Norris, Kessler's best friend in their native Bakersfield, California.