(AP) — Mike Stoops has built his entire career on hard-nosed defense, so it's not tough to understand the grimace on the Arizona coach's face after Southern California's Matt Barkley and Robert Woods cut another huge hole in the Wildcats' youthful unit.
Barkley passed for a school-record 468 yards and four touchdowns, Woods made 14 catches for 255 yards and two scores, and USC outlasted the Wildcats 48-41 Saturday, sending Arizona to its fourth straight loss.
Freshmen Marqise Lee and Xavier Grimble caught TD passes from Barkley, who also rushed for a score while breaking Carson Palmer's 2002 yardage record with a blistering performance against Arizona's maligned defense.
Despite another prolific afternoon from Nick Foles, who passed for 425 yards and four touchdowns, the Wildcats (1-4, 0-3) have given up 178 points in the last four games, all losses.
"Defense continues to be our issue," Stoops said. "Our inability to stop them just periodically — not consistently, just periodically, would give us a chance, but we just lack playmakers right now. We're very young and inexperienced on defense."
Arizona was whipped by top-10 opponents Oklahoma State, Stanford and Oregon in the previous three weeks, but the inconsistent Trojans were equally tough — at least on offense. USC never even had to punt, but it needed almost every yard against Foles' offense, which scored 29 points in the second half and nearly rallied Arizona to a win.
"You saw what our offense can do," Stoops said. "Our issues right now are on defense. Until we play good defense, it's hard to win."
Ka'Deem Carey rushed for two touchdowns and caught another scoring pass for the Wildcats, who haven't beaten an FBS opponent in nearly a year.
At least the schedule gets a bit less murderous now, with a trip to Oregon State followed by a bye and a home game against UCLA.
Keola Antolin rushed for 87 yards for Arizona, while star receiver Juron Criner was limited to three catches for 29 yards and a touchdown. Foles went 41 for 53, but two drive-killing first-quarter interceptions — his first two picks of the season — and two failed extra points by struggling kicker Alex Zendejas allowed USC to pull away with a 27-12 halftime lead.
"I forced a couple of throws," Foles said. "I tried to get the ball downfield, and it didn't work out how I wanted to, but I thought after the slow start we were doing well on offense and moving the ball. We have a lot to improve on."
USC's defense wasn't much better, aside from those two interceptions by T.J. McDonald, but the Trojans (4-1, 2-1 Pac-12) outgained Arizona 582-554 to stay unbeaten in four home games.
Barkley went 32 for 39 with one interception, bouncing back from a rough start at Arizona State last week with another landmark game. After setting USC's single-game record for completions in the season opener, the junior has thrown nine TD passes in his last two home games.
"It didn't feel like I was breaking a record, because it was such a tight game going back and forth," Barkley said. "It's crazy to think about, because I grew up looking up to Carson Palmer. He's one of my heroes. I did want to be in his shoes someday, and now that I'm here, it's definitely a dream."
Woods is merely having the most prolific season by a receiver in USC's long history through five games, starting off this chapter with an 82-yard score on the Trojans' second play.
"Woods tore our zone up," Arizona cornerback Shaquille Richardson said.
The speedy sophomore, who set the USC mark with 17 catches in that season-opening win over Minnesota, fell 5 yards short of R. Jay Soward's 260-yard school record when Arizona held him to one catch for 2 yards in the fourth quarter.
"It's not a big assignment, because Matt is putting the ball on the money and on point every time," Woods said. "Run the route and catch the ball. He makes it so easy for us. Matt's putting the ball on the money, on point every time."
Woods took charge from USC's second play, catching a short pass from Barkley and splitting two defenders before outrunning the entire Arizona secondary down the sideline for a score. Lee caught a wide-open 38-yard TD pass from Barkley late in the first quarter when Arizona's entire defense appeared to focus on Woods, and Grimble caught a 7-yard scoring strike midway through the second quarter.
Arizona's spread offense also moved the ball easily against USC, punting just once in the first three quarters — but Foles' mistakes put the Wildcats in a huge hole. Foles' first interception of the season killed the Wildcats' second drive in USC territory, and Foles badly overthrew David Douglas in the Trojans' end on the next drive.
After Curtis McNeal rushed for 9-yard score with 9:28 to play to put the Trojans up by 14 points, USC turned the ball over on downs at midfield in the closing minutes. Austin Hill caught a 4-yard TD pass from Foles with 1 minute to play, but McDonald recovered an onside kick to seal it.
USC has won nine of its last 10 meetings with the Wildcats, who won in their last visit to the Coliseum two years ago.