NORMAN, Okla. (AP) -- Sam Bradford's debut as Oklahoma's starting quarterback couldn't have looked much better if he had scripted it himself.

In his first start, the redshirt freshman tied a record set by one Heisman Trophy winner and broke another set by a Heisman runner-up, throwing for 363 yards and three touchdowns as the No. 8 Sooners beat North Texas 79-10 Saturday night.

"This really is what you dream about, coming out here and playing in front of 85,000 and getting a win like that," Bradford said. "There's not going to be many nights like this. You've got to take these. These are special."

Freshman DeMarco Murray became the first Oklahoma player to score five touchdowns in his debut, and the Sooners showed no signs of a hangover following a stunning overtime loss to Boise State in the Fiesta Bowl and the loss of star tailback Adrian Peterson to the NFL.

Bradford needed only 32 seconds to notch his first career touchdown pass, a 15-yarder to tight end Jermaine Gresham as he slinged the ball along the line of scrimmage for three straight plays and allowed his receivers to run for big gains.

Bradford broke Josh Heupel's record for passing yardage in a half that was set against Baylor in 2000, going 20-for-22 for 350 yards in the first half. Heupel was second in the Heisman voting in 2000.

Bradford completed his only pass in the second half to tie 2003 Heisman Trophy winner Jason White's school record of 18 straight completions, then yielded to backup Joey Halzle.

"Once I got in that rhythm, I felt like, `I know where I'm going, I know where it's going to be, so here it comes," Bradford said.

Murray added four touchdown runs by the end of the first half, and coach Bob Stoops called timeout with under 2 minutes remaining to preserve time for one last score. Bradford's 24-yard lob to Malcolm Kelly made it 49-0 as the Sooners received a standing ovation for nearly hanging Barry Switzer's proverbial "half a hundred" on the Mean Green before halftime.

Oklahoma ended up with its most lopsided win in a season opener since it beat New Mexico State 73-3 to start the 1989 season and its second-highest point total since 1919.

It was a rough welcome to big-time college football for new North Texas coach Todd Dodge, who is making the transition from high school this season.

Dodge, who led Texas high-school powerhouse Southlake Carroll to three straight state titles, lost for the first time since the 2003 state championship game. He'd been 79-1 in his last five seasons at Carroll.

"We have a perspective on it," Stoops said. "I think coach Dodge will do a great job at North Texas, I really do. They just need time."

Next up for the Sooners is Miami, which beat Marshall 31-3 Saturday.

"There's a lot of room for improvement," Bradford said. "You have to get better each week. If you're not getting better, you're getting worse."

On the first play of the game, Bradford had to scramble to his right before getting knocked out of bounds and slamming into a metal bench on the sidelines. It was the only time he seemed frantic the whole game.

"I got over there and got pushed out of bounds, and I think once I got that I was in the game," Bradford said. "I was back in it. I felt good after that."

Murray made Peterson, the 2004 Heisman runner-up, seem forgettable. He lined up as a wide receiver and scored his first career touchdown on a 44-yard end around, then finished off four more drives with short runs in goal line situations.

The school record is Quentin Griffin's six touchdowns in Oklahoma's 63-14 win against Texas in 2000. Murray, who became the primary ball carrier after Allen Patrick sprained his ankle and Chris Brown was suspended, totaled 87 yards on 17 carries.

Juaquin Iglesias caught seven passes for 128 yards, and Kelly had four catches for 118 yards. Kelly also scored on a 65-yard catch in the second quarter.

Stoops said the Sooners were trying not to embarrass North Texas late in the game.

"We were telling the guys even if they break something, don't score. Take a knee or get down at some point," Stoops said.

Giovanni Vizza, who lost a quarterback competition for North Texas against Daniel Meager, entered in the third quarter and set up Thomas Moreland's 29-yard field goal to break up the shutout. He added a 69-yard touchdown pass to Casey Fitzgerald.

He also threw two interceptions, including one that was returned 25 yards for a score by Nic Harris. Jamario Thomas, the 2004 NCAA rushing champion, ran only five times for four yards.

The Mean Green are 0-14 against top 10 teams. Five of those losses came in season openers against Oklahoma and Texas within the past six years.