LOS ANGELES (Ticker) -- One week after surviving a scare, Southern California was frightening.
Matt Leinart threw four touchdown passes - all in the first half - and Reggie Bush was an unstoppable quadruple threat as USC looked every bit like a top-ranked team in a 45-7 Pac-10 Conference demolition of No. 19 Arizona State.
A week ago here, the Trojans were outplayed by California but held on for a 23-17 win as a late fourth-down pass into the end zone fell incomplete. The narrow win cost the defending national co-champions some first-place votes in both polls.
Two days before the release of the first BCS rankings, the Trojans (6-0, 3-0 Pac-10) wasted no time answering any questions about their status as the nation's No. 1 team. They scored on their first two possessions en route to a 42-7 halftime lead over a previously unbeaten Arizona State squad that was coming off a bye and did not look sharp.
"We needed to win this game convincingly because a lot of our games have been close," Bush said. "We needed to win convincingly to show that we're the No. 1 team in the nation."
"The advantage of a bye week is so that you can become familiar with what they do and we didn't capitalize," Sun Devils center Drew Hodgson said.
Leinart completed 13-of-24 passes for 224 yards. He was absolutely sparkling in the first half, softening up ASU with short passes before striking deep later on.
"He did a great job moving the ball around," USC coach Pete Carroll said. "He's the leader of this team, no doubt about it."
Bush had 21 yards on five carries and 45 yards on two catches while expanding his all-around skills. The tailback atoned for a fumbled punt return that positioned Arizona State for its first score with a long run that set up a touchdown, a 52-yard TD pass to freshman Dwayne Jarrett and a 41-yard punt return that led to Leinart's 34-yard TD pass to Jarrett just before the half.
Both Leinart and Bush sat for the entire fourth quarter of USC's 15th straight win.
"Today was a sign of what we can do with a good game plan," said Leinart, who has 44 TD passes and just six interceptions during the streak. "We wanted a lot of 1-on-1 coverage with our receivers and we exploited it."
Stepping in for Steve Smith, who suffered a broken leg against California, Jarrett caught five passes for 139 yards and three TDs.
"Dwayne right now is getting over the hump," Carroll said. "He's not just out there competing, he's making plays. He's a fantastic player."
The Trojans also were solid on defense. They limited the Sun Devils (5-1, 2-1) to just 24 rushing yards and 243 overall.
"I didn't think we would get totally stoned in the running game in the first half," ASU coach Dirk Koetter said. "We couldn't get two inches."
Leinart capped USC's first drive with a 10-yard TD pass to Bush on a slant pattern less than five minutes into the contest. After the Sun Devils missed a field goal, Leinart struck again with a nine-yard scoring pass to tailback LenDale White, who bulled over two defenders and into the end zone with 1:10 left in the first period.
Early in the second quarter, ASU's Andrew Walter was picked off by linebacker Matt Grootegoed, who returned his fourth interception of the season 21 yards to the 19. On the next play, Leinart hit Jarrett on a fade pattern, and the rout was on.
"At that point, I think a little doubt creeped in, and you can't do that against a team like USC," Koetter said.
Bush's fumble gave the Sun Devils a short field, and they cashed in with Hakim Hill's two-yard TD run. But USC immediately answered as Bush had a 35-yard catch-and-run to set up Leinart's sneak that made it 28-7 with 5:08 before halftime.
On USC's next possession, Bush lined up left as a receiver, took an end around, pulled up and fired a long pass to a wide-open Jarrett, who pranced in untouched.
On Bush's punt return, he made several moves, reversed field and appeared to break free but stepped out of bounds avoiding a tackle. Leinart finished the job with his second TD pass to Jarrett.
USC scored 42 points in the first half for the first time since 1981 vs. Oregon State. Walter was 19-of-34 for 181 yards and two interceptions. He was sacked six times and held without a TD pass for the first time in 10 games.
"I didn't expect this," he said. "I really don't have any answers."