After going down in the first half, the Nittany Lions grinded out a win in their final regular season home game.
The top five teams are now Texas, Oregon, Penn State, Ohio State, and Georgia.
Warren had another record-breaking day against the Trojans.
"It was unbelievable and an absolute dream come true."
Warren now holds the single-game school record for most receptions by an offensive player, passing DaeSean Hamilton who had 14 receptions in a game in 2014.
The Nittany Lions mounted a comeback bid in the third period but fell short.