Kedon Slovis threw an 8-yard touchdown to Amon-Ra St. Brown with 16 seconds left for his fifth passing TD of the game, and No. 16 Southern California rallied from an 18-point, third-quarter deficit to beat UCLA 43-38 on Saturday night.
UCLA took a 38-36 lead with 52 seconds remaining on Nicholas Barr-Mira's 43-yard field goal, but USC (5-0) answered quickly.
Gary Bryant returned the kickoff 63 yards to the Bruins 43, Slovis connected with Tyler Vaughns on a 35-yard reception and St. Brown caught his second TD of the game on the next play.
Local news from across Southern California
Slovis completed 30 of 47 passes for 344 yards with two touchdowns each to St. Brown and Drake London. Vaughns caught eight passes for 110 yards and Vavae Malepeai ran for 110 yards in the 90th Crosstown Showdown.
The Trojans clinched the Pac-12 South title earlier in the day when Utah beat Colorado.
The Trojans trailed 28-10 early in the third quarter before scoring touchdowns on five of their seven second-half drives. USC was still down 35-23 at the start of the fourth quarter before Malapei's 10-yard run, and London scored his second TD on a 9-yard reception. USC went for two after London's score but couldn't convert.
USC was able to rally due to UCLA (3-3) mistakes. The Bruins twice turned it over on downs, fumbled on a fake punt and Dorian Thompson-Robinson was picked off.
Thompson-Robinson was 30 of 36 for 364 yards with four touchdowns and two interceptions. Demetric Felton rushed for 90 yards and had two TDs receiving, and Craig Dulcich had eight receptions for 167 yards.
After Brittain Brown's 15-yard run put the Bruins up by more than two touchdowns, USC scored 13 straight points on Slovis' TD passes to Vaughns and St. Brown. The Bruins went up 35-23 when Thompson-Robinson connected with Dulcich for a 69-yard score one play after Slovis was intercepted by Stephan Blaylock.
Felton gave the Bruins a 14-0 lead with 8:41 remaining in the first half on a 21-yard reception. After USC scored 10 straight points which included a 65-yard connection from Slovis to London, Felton put UCLA up 21-10 at halftime on a 12-yard grab with 20 seconds remaining in the first half.
Talanoa Hufanga intercepted a pass for the fourth straight game during the fourth quarter, which led to London's second touchdown.
Fernea, a redshirt senior, scored only the second touchdown of his career on a quick screen pass that went for 33 yards.
The Bruins lined up trips left and Fernea got great blocks from Dulcich and Logan Loya to go untouched. It was only his second reception of the season and eighth of his career.
PLAY OF THE GAME
London put the Trojans on the board with one of the best individual effort plays of the season. On second-and-14 from the USC 35, Slovis stepped up in the pocket and found London downfield.
The sophomore caught it at the UCLA 33 and then shed six tackles en route to the end zone, including four attempts at trying to take him down in the final 10 yards.
USC: The Trojans had a tough game but should go up a couple spots in the rankings.
UCLA: When the Bruins play clean football, they are usually able to win, but too many mistakes in the second half allowed the Trojans to rally and win for the second straight season.
USC: Will host Pac-12 championship game on Friday vs. Washington.