UCLA is still unbeaten, thanks to a quarterback who had not thrown a pass all season.

The No. 21 Bruins beat No. 13 Oregon 17-15 on Saturday at Autzen Stadium in Eugene, the Associated Press reported via ABC News. UCLA is now 5-0.

Starting quarterback Nico Iamaleava was hurt and did not start the second half, ESPN reported. Backup Ty Dieffenbach came in. He had been a third-stringer at one point.

"When I heard that, I was just tunnel-visioned and ready to go execute," Dieffenbach told the New York Post. "I've been waiting for this moment. I'm ready."

He threw a 9-yard touchdown pass to running back Wayne Knight in the fourth quarter. Knight also ran for a touchdown. He finished with 103 rushing yards on 22 carries and caught three passes.

It was a sloppy game, with 10 turnovers in all. Oregon gave the ball away seven times. The Ducks fell to 3-2 and 1-1 in the Big Ten.

Autzen Stadium is known as one of the loudest and toughest places to play in college football. The game was in front of a sellout crowd and on national TV. The Post called Dieffenbach's effort "a gutsy performance for the ages."

The win is a big moment for UCLA, which has struggled in recent seasons. The Bruins' status for coming games will depend on how badly Iamaleava is hurt. The team did not give details on his injury right away.

Oregon, a national power in recent years, now has two losses and faces a hard road to the playoff.

What we know: backup Ty Dieffenbach led UCLA to a 17-15 win.
What we don't: how badly Iamaleava is hurt.