If you thought the Arizona defense looked confused on Saturday night against Southern California, you weren’t alone. Linebacker Paul Vassallo thought so too.

“I don’t know if it’s any one thing,” Vassallo said. “I don’t have that answer. I just know we need to do better.”

Two weeks ago, the Arizona Wildcats were a top-10 team grounded by its defense, locked in a battle for the Pacific 10 Conference title.

Now, the Wildcats’ defense has vanished into a defense giving up more than 200 rushing yards in each of its last two games and six total rushing touchdowns, leaving fans wondering where the stout defense that once sat among the nation’s top-five went.

“I think it’s a good time for us to re-group,” said head coach Mike Stoops. “I think we’ve got to get some identity back to what we’re doing offensively and defensively.”

On Saturday, USC’s Marc Tyler had a career night in yardage and carries, 160 and 31 respectively. He picked apart Arizona’s front seven, finding gaps and getting push at the point of attack to move the pile forward.

Tyler’s performance was typical of the type of plays that have started to plague the defense in recent weeks.

“I think it has to do more with our inability to stop it,” Stoops said about the defense’s problems with stopping the run. “We never consistently stopped the run and that led to our demise, obviously, defensively.”

It hasn’t been so much the amount of yardage the defense has given up — Arizona’s average was bound to go up once they started facing top-tier conference teams — but it’s been how the Wildcats have give up that yardage.

Failing to get off the field on 3rd-and-medium yardage, giving up long runs, missing tackles — all things that would have been considered uncharacteristic earlier the year after the Wildcats’ surprising defensive start.

Stoops said that some of Arizona’s recent problems have been with defensive discipline, something that cornerback Robert Golden echoed.

“We just got to go out there and compete more. I feel like the guys wasn’t out there,” Golden said. “We didn’t have that intensity that we usually have. I just know we’ve got to go out there and compete more.”

Arizona’s opponents are converting on two-thirds of their third down attempts. Both Stanford and USC had the ball for more than 37 minutes, nearly 15 minutes longer than Arizona in each game.

“We need to get back to work and get back to playing the prideful defense that we did the first seven, eight weeks and just figure it out,” Vassallo said. “We like to think of it as we’re making the mistakes and they’re not better than us, it’s just we’re beating ourselves.”

So where has the Wildcats’ identity of a pass-rushing, quarterback-sacking, run-stopping gone in the last two weeks?

The Wildcats will have to answer that question during their bye week as they prepare for Oregon.

If Arizona wants any chance of hanging with the No. 1 Ducks, a team that puts up 51 points per game and sports the nation’s top rusher LaMichael James, the defense that stopped Iowa and California will show up to Eugene, Ore.

“Get back to our basics, get ready for another rough game,” said safety Adam Hall of what the defense will work on during the bye. “We just need to get back to the things we pride ourselves on — getting off the field on third down, making plays and just physical game.”