USC’s defense is pumped up in 38-17 victory

USC could have been deflated.

The Trojans had lost two games in a row. They spent a week absorbing blows for their defensive performance against Oregon and for using illegally deflated balls against the Ducks. And now, boos were raining down upon their sputtering offense during the first half of Saturday’s game against Arizona State at the Coliseum.

But No. 21 USC regrouped at halftime, got a lift from senior tailback Curtis McNeal and rode a pumped-up defense to a 38-17 victory that kept the Trojans in the hunt for the Rose Bowl.

“It wasn’t a perfect game,” Coach Lane Kiffin noted, but he was happy with the result.

“Just imagine what this press conference would be like,” he quipped, “if it went the other way.”

USC improved to 7-3 overall and 5-3 in the Pac-12 heading into Saturday’s game against No. 17 UCLA.

A victory over the Bruins will advance USC to the Pac-12 title game Nov. 30.

“A lot has gone on this year, both on and off the field,” senior quarterback Matt Barkley said. “And I think our guys have done a great job — at this moment — of really focusing on what matters.

“And that’s to win these games and decide our future, which we can do.”

The Trojans won Saturday despite five turnovers, including Barkley’s first three-interception game since his freshman season.

The smallish McNeal played a big role, the senior rushing for 163 yards in 31 carries and scoring three second-half touchdowns as USC overcame a 17-14 third-quarter deficit.

Receiver Marqise Lee kept his new Heisman Trophy campaign going by scoring on an 80-yard touchdown pass play in the first quarter and amassing 227 all-purpose yards.

But it was the defense that seemed most pleased with the victory.

“We were just tired of losing,” said defensive lineman Leonard Williams, who had one of the Trojans’ three interceptions.

After giving up a record 730 yards against Oregon, the Trojans held Arizona’s spread offense to 250.

Monte Kiffin, the Trojans’ embattled assistant head coach for defense, appeared relieved after directing a unit that recorded seven sacks.

“What a difference a week makes,” he said.

It looked like it might be a repeat of last week’s 62-51 loss to Oregon after Lee caught a pass and fumbled on the Trojans’ first offensive play.

Arizona State (5-5 overall, 3-4 in the Pac-12) scored on Taylor Kelly’s 34-yard touchdown pass to Chris Coyle for a quick lead before Lee answered by taking a mid-range pass from Barkley and turning it into a spectacular touchdown.

Safety Aiden Darby put the Sun Devils ahead by intercepting a Barkley pass intended for Lee and returning it 70 yards for a touchdown. Barkley’s four-yard touchdown pass to tight end Xavier Grimble with less than a minute left in the first half tied the score, but the announced crowd of 80,154 did not sound very happy.

“It was very critical to have success in the third quarter there, obviously, just to get some juice back in the stadium,” Lane Kiffin said.

It did not start well.

Arizona State defensive lineman Carl Bradford tipped and intercepted Barkley’s pass on the first play of the second half, setting up a field goal that gave Arizona State the lead.

“Our whole goal was to confuse and pressure the quarterback,” Arizona State Coach Todd Graham said. “And I thought we did that.”

But with Silas Redd out because of an undisclosed injury, McNeal ran for a touchdown, scored on a screen pass and ran for another touchdown while the defense shut down the Sun Devils.

“We knew we had to get back on track and prove to the country that what we put on tape last week is not the Trojans defense,” linebacker Dion Bailey said.

Now, it’s on to UCLA.

Last season, USC defeated the Bruins, 50-0. It was the Trojans’ season finale because they were in the final year of a two-year bowl ban.

But a victory Saturday at the Rose Bowl could earn USC a possible rematch with second-ranked Oregon in the Pac-12 title game.

“We control our own destiny,” Barkley said. “It’s a playoff in a sense.”

gary.klein@latimes.com

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