USC started play Saturday down two main linebackers with Eric Gentry and Mason Cobb out with unspecified injuries. The Trojans would lose another linebacker in the second quarter when Tackett Curtis was ejected for targeting.

And yet, there were no excuses needed for the team's much-maligned defense.

Outside of a 73-yard reception in which Nevada's Spencer Curtis simply beat cornerback Domani Jackson in tight coverage down the sideline, setting up a short Wolf Pack touchdown, the visitors didn't score again and had trouble even mounting sustained drives.

This was exactly the kind of complete performance the No. 6-ranked Trojans needed in this kind of lopsided matchup as they did their part on both sides of the ball to close out a 66-14 win inside the Coliseum.

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USC (2-0) delivered 5 three-and-outs and forced 6 punts, a turnover on downs, two long missed field goals that didn't come close to the uprights and a punctuating defensive touchdown in the fourth quarter when Braylan Shelby forced a fumble on a sack and Stanley Ta'ufo'ou returned it 23 yards for the score. The Trojans held Nevada to 360 yards overall.

"As a defense, you go out and that mindset, you got a good offense, they're going to go out there and score, so for us we've got to hold that to our standard and know that's an advantage and what we have to do is go out there and give the ball back to them," nickel Jaylin Smith said.

And when they did give the ball back to the offense, well, quarterback Caleb Williams put on another show, completing 18 of 24 passes for 319 yards, 5 touchdowns and 0 interceptions (plus 42 rushing yards) before giving way to backup Miller Moss late in the third quarter.

"That's just Caleb being Caleb," receiver Mario Williams said.

Williams started the game with consecutive completions of 11 yards (to Mario Williams), 30 yards (Dorian Singer on a one-handed catch down the sideline), 21 yards (Mario Williams) and a 22-yard touchdown thrown perfectly over the shoulder to star freshman Zachariah Branch in the end zone.

After a punt on their next possession, the Trojans scored touchdowns on four straight series -- a 24-yard scoring scamper by MarShawn Lloyd, a 22-yard catch-and-run pass to Washington across the middle, a 15-yard fake-handoff and wide-open pass to Michael Jackson III in the end zone and a 13-yard completion to Rice after Williams danced in the pocket for an eternity and made a defender look silly before spotting Rice for the easy score.

That made it 35-7 at halftime.

Williams added a 45-yard touchdown to Washington, who had gotten behind the defense down the left sideline, early in the third quarter to push the lead to 42-7.

Williams tied Matt Barkley's USC record with his 11th 4-touchdown game -- achieving that feat in 31 fewer games than Barkley.

Ta'ufo'ou's fumble return for touchdown gave USC a 52-7 lead early in the fourth quarter, at which point the Trojans had only allowed 222 yards.

"Obviously, Stanley's fumble return was probably the major highlight of the game. When big people score, football's more fun. So that was awesome," Riley said.

Smith, meanwhile, said the sideline "erupted" and that Riley was jumping up and down.

Asked if he had pegged Ta'ufo'ou to score the first defensive touchdown of the season, Smith laughed.

"Most definitely not. It was crazy," he said.

On the ensuing drive, Nevada backup QB AJ Bianco threw a 77-yard touchdown pass to Jamaal Bell down the left sideline as he beat third-string safety Anthony Beavers.

Still, it was a step forward for the defense overall.

"You saw the run defense was, I mean, was really stout all night. Really, we gave up two fade balls. I mean, you don't discount those -- those can't happen, we have to get better. Other than that we played pretty clean football," Riley said.

Said defensive end Solomon Byrd: "We just played more consistent with our techniques and just being more disciplined. I don't think we did anything outside of ourselves -- just more disciplined."

And the offense wasn't done either -- freshman running back Quinten Joyner ripped off a 47-yard touchdown run with 9:09 left in the fourth quarter to make it 59-14.

Fellow freshman Duce Robinson scored a 71-yard touchdown after catching a pass from Moss with 4:02 left to play pushing the Trojans to the 66-point mark.

Overall, Lloyd led USC with 76 rushing yards and a TD on just 7 carries along with 2 catches for 59 yards. Joyner had 4 carries for 65 yards and a TD. Washington had 3 catches for 75 yards and 2 TDs and Mario Williams had 4 catches for 66 yards.

USC finished the game with 668 total yards of offense in Saturday's win.

Through two games, Washington has 5 catches for 160 yards and 3 touchdowns.

"Just being assignment sound, being where [Williams] needs me to be, just making plays after that," Washington said simply of his strong start.

Playing a Nevada team that went 2-10 last year and lost its final 10 games, this is exactly what the Trojans were supposed to do, but nonetheless it was a confidence-builder in some key areas for the team.

Stanford awaits next weekend.

"I just gauge it by our team. You've been around these guys a lot now, you're starting to get a feel for these guys, where they're at individually, where they're at collectively, what we can be. For us, it's just a steady climb, right? We can't beat anybody until we play them, so you've got to continue throughout the year," Riley said. "I do think we took some really positive steps tonight, but in college football every week is its own story. You scrap it, you learn a few things and then you start over and the matchups and challenges are going to continue to change.

"We know we got a good one coming in here next Saturday night. We need this place rocking. Next Saturday at 7:30, we need this place rocking -- potentially the last time these schools match up for a long time and there's a lot of significance to that. And having that one here at home behind a great home crowd is very important."

NOTES: In addition to Gentry and Cobb, USC was also without defensive lineman Tyrone Taleni for a second straight game and slot receiver Raleek Brown was not spotted with the team during warmups. Offensive guard Gino Quinones was helped off the field in the first half, limping to the sideline and later returned with a big knee brace.

Riley didn't have an immediate update on Quinones but expressed optimism that the linebackers won't be out long.

Cobb and Gentry we don't think they're long-term. They weren't ready to go today. That had nothing to do with the opponent. I don't believe they would have played regardless -- they just weren't ready," he said. "And I thought guys stepped up. Shane Lee stepped up and played well, Raesjon [Davis] stepped up and played well. Tackett was doing some really nice things before the ejection. So no, I thought the guys really stepped up, communicated."