No. 14 Tulane stunned No. 8 USC and Heisman Trophy winner Caleb Williams with 16 points in the final 4:07 left in the game to win the Cotton Bowl 46-45.

With the win, Willie Fritz’s Green Wave completed the biggest turnaround in FBS history, improving to 12-2 this season a year after finishing 2-10.

“This is a huge win for Tulane,” he said after the game. “This is big. This program has had success at times. It’s big for the university, for the city, and, obviously, this football program.”

Tulane tight end Alex Bauman caught a 6-yard touchdown from Michael Pratt with 9 seconds left to cap a frantic finish.

Bauman’s contested catch, with linebacker Eric Gentry draped over him, was initially ruled an incompletion, but a replay review showed the ball never touched the ground as the players rolled over in the end zone. The Green Wave scored 16 points in the final 4:07, the game-winning touchdown coming after they got the ball back following a safety.

Fritz was asked right after the game, “What just happened?”

“I’m not sure,” he replied.

“I might have had a heart attack,” Fritz added.

Williams was 37-for-52 passing for 462 yards and a Cotton Bowl-record five touchdowns, exactly one month after the quarterback suffered a hamstring injury in USC’s loss to Utah in the Pac-12 championship game that kept the Trojans from making the four-team College Football Playoff.

Tyjae Spears ran for 205 yards and his career-best fourth touchdown started the final scoring surge for the American Athletic Conference champion Green Wave (12-2), who completed an FBS-record 10-win turnaround around after going 2-10 last season. They were in the New Year’s Six game as the highest-ranked Group of Five team.

After Spears’ 4-yard TD with 4:07 left, the Green Wave opted to kick deep instead of trying an onside kick. Mario Williams signaled for a fair catch, but fumbled the ball out of bounds at the 1. Two plays later, defensive tackle Patrick Jenkins met Austin Jones in the end zone and smothered him for a safety.

Pratt completed only 8 of 17 passes for 234 yards, but had two 24-yard completions on that final drive after the safety. The first one to Bauman converted a fourth-and-10, and Deuce Watts held on despite a crushing hit from a defender that left both of them on the ground after a 24-yard gain to the 6 with 18 seconds left.

After Williams followed coach Lincoln Riley from Oklahoma, the Trojans (11-3) matched the biggest turnaround in school history despite the coach’s first loss in six games at AT&T Stadium. It was a seven-win improvement over last season’s 4-8 record before Riley and Williams arrived on the West Coast.

The Associated Press contributed to this report.