Things looked good for Notre Dame then things turned sloppy then bad as the first half closed.
The Irish entered the break clinging to a 20-18 lead over Tulsa.
Notre Dame had a 20-12 lead after quarterback Tommy Rees, who is playing for the injured Dayne Crist, threw for his third touchdown of the game with 8:10 to play in the second quarter.
But on Rees' last two series he threw interceptions.
Crist is done for the season with a torn patella tendon in his left knee, according to reports from NBC.
"We are past that," coach Brian Kelly said before going into the locker room at halftime. "We are a little shorthanded, but we are going to keep fighting."
Rees started strong for the Irish when he came in about midway through the first quarter after Crist was injured at the end of a 29-yard run.
Rees completed 9 of 10 passes in the first quarter for 94 yards with two touchdowns.
Notre Dame used some trickery to set up Rees' third scoring throw.
From his own 41-yard line, Kelly called for a fake punt with freshman Bennett Jackson getting the ball.
The former New Jersey state hurdle champ ran the ball 20 yards, leaping over a defender at the end, to set up Notre Dame's second touchdown drive of the game.
Rees drilled Michael Floyd for a 4-yard touchdown with 8:10 to play in the first half.
The drive featured Rees hitting Tyler Eifert for 21 yards, and running back Robert Hughes playing quarterback out of the wildcat. Hughes had runs of three, five and one yard out of the wildcat.
Rees looks a lot more comfortable at quarterback than he did when he was called into the game against Michigan on Sept. 11. He has completed 18 of 29 passes for 179 yards, but the two interceptions to close the first half are disturbing.
Notre Dame's defense did a much better job against Tulsa in the second quarter. After giving up 143 yards in the first quarter, the Irish held the Golden Hurricane to 82 yards in the second quarter.
Tulsa's second-quarter touchdown came on a 66-yard return by Shawn Jackson. The Golden Hurricane failed on a two-point conversion attempt.