LOS ANGELES — Southern California had a nine-point lead with less than 3 minutes left. The 16th-ranked Trojans recovered two onside kicks and got a 53-yard touchdown run by Javorius Allen in the final moments.
And it still wasn't enough to avoid a jaw-dropping loss to Arizona State when the Trojans' once-vaunted pass defense came unglued one final time.
Bercovici capped his 510-yard, five-touchdown passing performance with his third scoring pass to Strong, who slipped in front of USC's Hayes Pullard at the goal line and pulled in the Hail Mary.
USC (3-2, 2-1 Pac-12) hadn't allowed a touchdown pass all year, but Strong jogged into the end zone untouched, celebrating in front of the Trojans' disbelieving fans.
"You learn the hard way in games like this," USC coach Steve Sarkisian said. "It was an awkward Hail Mary. The ball floated back to the middle of the field. It was a heck of a play by (Strong) tracking it."
Arizona State burned its three timeouts in the third quarter, but got the ball back at its 28 with 23 seconds left. Bercovici hit Gary Chambers for 26 yards before launching his final throw into a thicket of USC defenders.
USC also changed its defensive call late on the final play, leaving players confused.
"It was great execution by their offense," Pullard said. "(Strong) went up there and got the ball and got the job done."
Cody Kessler passed for 273 yards for the Trojans (3-2, 2-1), who led 34-25 after Allen's run. USC could have run out the clock after getting the ball back with 2:43 left, but couldn't get a first down before Kessler's short punt gave decent field position to the Sun Devils.
Kessler scrambled for an 8-yard TD in the fourth quarter, and Allen rushed for 143 yards and two TDs for the Trojans, who appeared to be on the way to an impressive win. USC's defense held the Pac-12's best rushing offense to 31 yards, a whopping 231 below its average.
Instead, Arizona State has won three of the schools' last four meetings, including a 62-41 victory in Tempe last season that led to USC coach Lane Kiffin's firing a few hours later. Sarkisian's first loss to the Sun Devils also stings in a totally different way.
"I'll be honest, it was a little bit of a prayer," said Bercovici, the San Fernando Valley product making his second start in front of dozens of friends and family.
"I just immediately fell to the floor. I saw Jaelen take a step in the end zone, and I don't think I could have made it down 50 yards to the end zone. It was an indescribable feeling. I've got people telling me, 'Get up, get up, get up!' But all I wanted to do was run upstairs to my mom and give her a big hug."
A week after giving up 62 points in a humbling loss to UCLA, the Sun Devils (4-1, 2-1 Pac-12) stormed the field to celebrate their first win at the Coliseum since 1999.
"That was the most unbelievable night I've ever had in coaching," Arizona State's Todd Graham said. "When he caught that ball, my heart stopped. You can be where we were last week, and be here this week."
Bercovici followed up his record-setting, 488-yard passing performance against UCLA with an even bigger night, also hitting Strong for a 77-yard TD midway through the second quarter while filling in for injured Taylor Kelly.
Arizona State couldn't get rolling on offense until just 6:26 remained. Bercovici hit D.J. Foster with a 21-yard touchdown pass, capping the 98-yard march.
Randall Telfer recovered the onside kick before Allen broke straight up the middle for his second scoring run. But Bercovici hit Cameron Smith for a 73-yard score moments later when cornerback Kevon Seymour misplayed the receiver.
Pullard recovered another onside kick, but USC couldn't move the ball. A poor punt by Kessler — who was kicking because USC's long snapper is injured — gave decent field position to the Sun Devils.
With the game-time temperature at 93 degrees during California's October heat wave, Nelson Agholor injected excitement into the first quarter with a 53-yard TD punt return.
USC was in command after a 79-yard scoring drive to open the fourth. Kessler avoided a sack and scrambled 8 yards through the heart of the defense, taking hits and stretching over the goal line.