Arizona falls to 6-3 overall and 4-2 in the Pac-12. USC improves to 8-2 and 6-1, respectively.
It snaps UA’s four-game winning streak and puts the Trojans in the driver’s seat for the Pac-12 South title.
After struggling on both sides of the ball in the first half, Arizona fell behind 28-6 with 6:04 left in the third quarter.
That’s when Khalil Tate and the Arizona offense, which tallied just 93 yards in the first half, regained the explosiveness it displayed in the previous four games.
The Wildcats scored on four straight drives to tie the game at 35 with 8:23 left in the fourth quarter.
But Sam Darnold and Ronald Jones II would answer with two scoring drives, and Tate would be intercepted twice in the late goings as the Trojans escaped with the victory.
USC outgained Arizona 642-380 as UA’s defense struggled yet again.
The Trojans averaged 6.4 yards per rush, and had two 100-yard rushers.
Jones ran for 194 yards and three touchdowns on 27 carries, while Aca'Cedric Ware had 14 carries for 122 yards and a touchdown.
Darnold, who appeared to be battling a hip injury, had a shaky start but finished 20 for 26 for 311 yards, two touchdowns, and an interception.
Aside from Dane Cruikshank’s pick in the end zone and a surprisingly decent mark on third down (5-12), the Trojans had little trouble moving the ball — a recurring theme for UA’s defense.
Arizona hardly pressured Darnold, while the defensive line was severely outplayed, giving USC’s talented running backs plenty of room to run.
Arizona’s offense had its fair share of struggles, too, but almost exclusively in the first half.
Arizona had nearly 300 yards in the second half, as Tate and company started to wear down a tiring USC defense.
Tate, whose touch down the field wasn’t nearly as crisp as usual, finished 14 for 31 for 146 yards, two touchdowns, and two interceptions.
He also ran for 161 yards and a touchdown on 26 carries, logging all but 73 of Arizona’s yards. He became the first Pac-12 quarterback to ever run for 1,000 yards.
However, in the first half, Tate looked more like the 17-year-old who played against the Trojans last season than the player in Heisman contention.
The sophomore was just 5 for 12 for 37 yards while rushing for 21 yards on 12 carries as USC stacked the box.
Arizona’s offensive line had surrendered just four sacks all season heading into Saturday’s game, but surrendered five to the Trojans.
While Lucas Havrisik made two 40-plus-yard field goals, Arizona’s special teams made a critical error in the game, allowing USC to block a punt and return it for a touchdown on UA’s first drive to put the Trojans up 7-0, which seemed to set the tone for the first two quarters.
It’s Arizona’s first loss since the 30-24 defeat vs. Utah on Sept. 23, but the good news is UA has three extremely winnable games left, starting with lowly Oregon State (1-8, 0-6 Pac-12) next Saturday in Tucson.
After that, Arizona will travel to Oregon and Arizona State to wrap up the regular season.
First half summary
Leaning on its ground game, USC moved the ball easily on its opening drive, but went for it on 4th-and-1 at the UA 17 and were stuffed on a QB sneak.
Then disaster happened for Arizona. The Wildcats went three-and-out and Josh Pollack’s punt attempt was blocked and returned for a touchdown to give USC an early 7-0 lead.
Arizona’s next drive ended after just four plays after Tate overshot a pair of receivers downfield, and USC subsequently drove 97 yards in nine plays, continuing to gash the Wildcats on the ground.
But the Trojans decided to pass as they neared the end zone for whatever reason, and Dane Cruikshank picked off Darnold in the end zone to take would-be points off the board (earlier in the drive, Jace Whittaker dropped a would-be pick six but there was roughing the passer on the play).
Arizona had success on the ground on its next drive, but Tate took a 13-yard sack on second down in USC territory before running for a 10-yard draw to set up a 45-yard field goal attempt.
Lucas Havrisik drilled it to make it 7-3.
Darnold started to heat up on USC’s next drive, leading the Trojans to an 11-play, 67-yard touchdown drive. Darnold connected on a 22-yard strike to a wide open Tyler Vaughns for the score.
Arizona would go three-and-out again, and four plays later the Trojans would be back in the end zone, with Darnold finding Steven Mitchell Jr. for a 27-yard touchdown.
USC outgained Arizona 308-93 in the first half, and completely dominated the trenches. The Trojans averaged 6.4 yards per carry and sacked Tate twice. Arizona had not allowed a sack for over a month heading into the game.
Havrisik made a 42-yard field goal with 2:13 left to make it a 21-6 game at the break.
After a shaky start, Darnold finished the first half 10 for 15 for 142 yards, two touchdowns, and an interception.
Tate, who struggled with his downfield accuracy, was 5 for 12 for 37 yards, and he rushed for just 21 yards on 12 carries.
J.J. Taylor had nine carries for 25 yards. Though listed as probable, Nick Wilson did not see any action until the second half.
The longest play for the Wildcats was a 12-yard catch by Shun Brown, as USC bottled up Arizona’s explosive offense.
Second half summary
Arizona went three-and-out on its opening drive but .... a taunting penalty on fourth down by the Trojans extended it.
The Wildcats would drive to the two-yard line, but Tate fumbled and USC recovered at its two-yard line, ending a long drive.
After the two teams traded punts, Darnold found Deontay Burnett for 41 yards, then Ronald Jones rushed for a five-yard touchdown to make it 28-6.
Tate answered, weaving for a 32-yard touchdown to make it 28-13, which the Arizona defense followed up with a three-and-out.
Tate broke for another long run, then rolled right and found Brown for a 30-yard touchdown to make it 28-20.
But USC’s offense responded with six, as Aca'Cedric Ware scampered for a 40-yard touchdown to push the Trojans lead up to 35-20 with 13:56 left in the fourth.
Tate ran for 54 yards on UA’s next play, and two plays later he found Taylor on a wheel route for a 16-yard touchdown.
An errant throw by Darnold on third down forced a USC punt, which Brown returned for 31 yards to the USC 47.
Tate and Arizona had no problem moving the ball, and Zach Green scored six plays later to make it 35-33. Tate then rolled right and found a leaping Tony Ellison for the game-tying two-point conversion.
But Darnold would find Jones for 33 yards down the far sideline to move USC into the red zone, and Jones would run it in from a yard out just a few moments later to give the Trojans the lead.
Arizona had a little over five minutes to tie the game, but Tate was intercepted, floating a pass down the middle of the field while the intended receiver Ellison broke toward the sideline.
Jones would run for 52 yards on the next play and would eventually tally another rushing touchdown to seal the game with 3:09 left.
Tate was picked off a second time on UA’s next drive.
Follow Ryan Kelapire on Twitter at @RKelapire