LOS ANGELES — Southern California’s defense has been among the nation’s most dominant, except in the second half of its last two games — and for coach Pete Carroll, that’s not dominant enough.

That formidable unit became ordinary after halftime against Notre Dame and Oregon State, leaving Carroll a bit concerned about his defense’s finishing skills heading into the No. 4 Trojans’ showdown with No. 10 Oregon on Halloween night.
“We haven’t done very well,” Carroll said Tuesday. “We have been really susceptible to them throwing out the football. Being out ahead didn’t help us any. We didn’t play well with the lead when the teams threw the football a bunch.”
Indeed, Notre Dame quarterback Jimmy Clausen and Oregon State’s Sean Canfield excelled while attempting to lead comebacks against the Trojans (6-1, 3-1 Pac-10), whose quest for a seventh consecutive Pac-10 title would be all but ended by a loss to the Ducks (6-1, 4-0).
Carroll is well aware defenses are at a disadvantage when a trailing team abandons the run during a comeback attempt. He knows yardage can get chewed up during come-from-behind surges — but he still doesn’t like it.
“When the teams decided they needed to throw the football to win, they did very well, and I think a lot has to do with the quarterbacks,” Carroll said. “The quarterbacks that we just played were fantastic throwers. They showed that.”
Oregon State followed up Notre Dame’s 285-yard passing game with 329 yards last weekend in USC’s 42-36 victory. The Trojans hadn’t given up more than 237 yards all season before those comebacks, which also led to the most first downs and the two biggest total offensive games by USC’s opponents this season.
Carroll’s players aren’t worried about their second-half struggles. Linebacker Chris Galippo described the defense’s mistakes against Oregon State as “rinky-dink things” that can easily be corrected before facing the Ducks.
“It wasn’t like they were constantly moving down the field and scoring on us,” defensive tackle Armond Armstead said. “The mistakes that were made can definitely be corrected. We know we have a good defense here, and we just need to play 60 minutes.
Oregon’s multifaceted offense is built around quarterback Jeremiah Masoli, who doesn’t much resemble Clausen or Canfield — two standout dropback passers with ample experience picking apart a defense. Masoli excels at running, and his pocket skills haven’t appeared to match the Trojans’ previous two opponents.
So Carroll is making sure his defense focuses primarily on stopping the run against the Ducks, who will have the full backing of their frenzied fans and the possibility of a steady rain in Eugene on Saturday night.
Yet USC is traditionally outstanding in its biggest games, both on the road and at the Coliseum. During Carroll’s tenure, the Trojans have lost more trap games against mediocre opponents than showdowns on the way to seven straight Pac-10 titles, although the coach can’t explain exactly why.
“The crowd is a factor when they are doing well,” Carroll said. “When the other team is doing really well, the crowd goes nuts. We have to play up to a level that doesn’t allow for that kind of excitement, and hopefully we will be able to do that. Once they catch fire, though, it can be more of a factor. We have done well over the years. We have kept games close and played solidly and finished well, and so hopefully we’ll be able to do that again.”