Notre Dame cut its deficit to South Florida to 16-7 after the third quarter Saturday.
Notre Dame finally scored on its second drive of the second half with a new quarterback under center.
Tommy Rees, who replaced Dayne Crist at quarterback to start the second half, hit Michael Floyd for a 24-yard score to cut South Florida's lead to 16-7 with 7:12 left in the third.
Rees' first series ended with an interception when his pass bounced off receiver TJ Jones and into the hands of a Bulls defender.
Rees finished the third quarter completing 10 of 14 passes for 140 yards with a touchdown and an interception, that was more on the receiver than him.