NORMAN — Javon Harris knows well all of the mistakes he made that cost him a spot in the starting lineup and landed him at the center of the criticism of Oklahoma's pass defense.

All that is behind him now.

Harris and the retooled Sooners' secondary are off to a strong start this season, ranking ninth in the nation in passing defense after a brutal finish to 2011. In the first big test for the secondary this season, Harris came up with one of the team's three interceptions and returned it 46 yards for a touchdown that put Oklahoma comfortably ahead of Texas Tech in the third quarter of a 41-20 win on Saturday.

That avenged a loss to the Red Raiders a season ago, when the Sooners were gashed for 452 yards through the air, that was one of several poor performance that stuck with Harris and the rest of the secondary throughout the offseason.

"We stayed on each other about each and every thing that we needed to do and just took it over to this year," Harris said. "We know that last year was last year. We don't dwell on things that happened last year, just like we don't dwell on things that happen game to game. We just go in there and try to get better each week. We correct each other.

"We're brothers out there. If somebody's messing up, if somebody needs to work on something, we tell each other. It's all about the love. You've got to love the game. You've got to love each other."

Oklahoma headed into this season with the same players in the starting lineup that struggled at times last season, but new defensive coordinator Mike Stoops shuffled them around into places he thought suited them better. Aaron Colvin switched from safety to cornerback, Tony Jefferson from nickelback to free safety and Gabe Lynn from cornerback to nickelback.

Harris was bumped from free safety back to strong safety, where he had played prior to last season.

"It's not really just a switching positions thing for me. It was really a mindset," Harris said. "I just wanted to come in this season with the mindset of, 'Go out here and get it. No holding back, can't look back, finish strong and get better.' That's the only thing I can do."

Harris' struggles last season centered around getting caught looking into the backfield. As the free safety, his responsibility was not to let anyone get behind him. But in a 45-38 loss to Baylor, he was burnt deep twice as eventual Heisman Trophy winner Robert Griffin III threw for 485 yards and four touchdowns.

Harris paid the price, losing his place in the starting lineup for the final three games of the season. He headed into his senior season with one last chance to get it right.

"I would say that I'm just a player trying to make it, but at the same time just want to continue to lead my guys and just get better every game," Harris said. "Consistency was one word that I used at the beginning of the year. I just want to go and finish this year out. Last year, I didn't get to finish the year out.

"One thing about my character is to finish strong, and that's what I plan on doing."

Heading into Saturday's Red River Rivalry game against No. 15 Texas (4-1, 1-1 Big 12) in Dallas, the 13th-ranked Sooners (3-1, 1-1) are allowing only 160.5 passing yards per game with just one touchdown pass. Three of the nation's top five passing teams — West Virginia, Baylor and Oklahoma State — remain on the schedule and Texas has shown improvement with David Ash taking over as the starting quarterback on a full-time basis.

"We just have to keep that mentality for the rest of the season," cornerback Demontre Hurst said. "We've got a long season, we've got teams that's really going to try and throw the ball and test us."

The Texas Tech game was only a start. The Sooners limited Seth Doege to 203 yards — less than half what he had in Norman a season earlier — before backup Michael Brewer threw for 68 yards in mop-up duty against Oklahoma's backups.

"That right there just shows that we can stay on the same page," Harris said. "We'll go into this game and we'll go in each week the same way. ...

"This is a no-fly zone. Anything that's going in the air is going to get struck down or is coming back the other way."

Harris, a former running back at MacArthur High School in Lawton, scored his first career touchdown with the interception that was tipped off the hands of Tech receiver Eric Ward and right to him.

"He definitely finds the ball and that goes with preparation. He's always in the right place at the right time," said Colvin, who had his first career interception in the game. "Things don't happen just for no reason. I feel like your preparation allows you to do some of the things and I feel like that's why he makes a lot of plays."