CHAPEL HILL, N.C. -- Mitch Trubisky joked that it must have been the haircut he got Friday. Whatever the reason, he was razor sharp.
Trubisky came off the bench and threw four second-half touchdown passes to help North Carolina beat Delaware 41-14 on Saturday.
Trubisky completed 17 of 20 passes for 312 yards, all career-high marks, and set a school record for single-game pass efficiency rating. He also added 39 rushing yards on six attempts.
"Everyone else played really hard, so it made my job easy," Trubisky said.
Mack Hollins caught touchdown passes of 33 and 64 yards for the Tar Heels (3-1), who closed the nonconference portion of their schedule with three consecutive wins.
Thomas Jefferson rushed for 163 yards and two touchdowns for the Blue Hens (1-3).
Trubisky took over for starting quarterback Marquise Williams on North Carolina's final possession of the first half.
Williams, who was sacked for an 11-yard loss on his final play, spent the second half on the sideline. He walked gingerly but showed no other sign of injury as he conversed with teammates and coaches during the final two quarters.
"I wasn't happy with the way we were executing, so we put Mitch in," North Carolina coach Larry Fedora said. "Mitch ran the offense well and did a nice job, so I decided to leave him in."
Asked whether Williams was injured, Fedora said, "I don't know. I have no idea." Fedora also said he didn't know whether Williams could have played in the second half.
Williams, a senior who set 18 school records last season, was not made available to the media after the game.
Fedora interrupted a question about the identity of his starting quarterback moving forward.
"As of right now, there are no changes," he said.
Trubisky threw touchdown passes on four consecutive possessions over a 19-minute span to help the Tar Heels turn a close game into a rout.
He started the barrage with two deep scoring passes to Hollins over the top of Delaware's defense. Trubisky hit Bug Howard with a 10-yard strike early in the fourth quarter and then found Ryan Switzer for a 63-yard score on a nifty catch and run.
He had support from Williams the whole way.
"We're really close," Trubisky said. "He just said, It's your time. Roll, baby.' He had my back."
The Tar Heels racked up 568 total yards and finished a game without punting for the first time since 1994.
Jefferson silenced the sparse, rain-soaked crowd on the second play by ripping off a 72-yard touchdown run. He broke a tackle in the backfield and then streaked untouched to the end zone for the longest run by a freshman in program history.
"When you get a little positive reinforcement like we did on the second play and you pop a run, that helps everybody's confidence, everybody's enthusiasm," said Delaware coach Dave Brock, an assistant coach at North Carolina from 2005-06.
The Tar Heels tied the game with an 18-yard touchdown run by Williams on their first possession, but their high-powered offense was stuck in the mud in soggy conditions for much of the first half.
Nick Weiler converted field-goal attempts of 46 and 26 yards to give North Carolina a 13-7 lead at halftime
The Blue Hens kept the game close for almost three quarters despite featuring a one-dimensional offense. They finished with 279 rushing yards, but quarterback Joe Walker completed 4 of 10 passes for just 24 yards.
"I felt like we had opportunities to do more than we did, and we have got to make the corrections," Brock said.
AP College Football website: www.collegefootball.ap.org