TUCSON, Ariz. -- As a tense night in the desert wore on, Southern California's defenders decided no one was going to beat them.
Not the Arizona Wildcats or the Trojans' sputtering offense.
The defense carried the fifth-ranked Trojans to a hard-nosed 17-10 victory over the Wildcats, keeping USC's national title hopes alive.
"We like it to be a defensive battle," linebacker Rey Maualuga said. "Not one person can do it by themselves. We came in, we answered the call and we did a great job."
The Trojans (6-1, 4-1 Pac-10) needed a victory to keep pace with the four teams ahead of them in the Bowl Championship Series standings, all of whom won Saturday.
The game matched two of the four teams tied for the Pac-10 lead midway through the season -- the upstart Wildcats, who haven't been to a bowl game since 1998, and dominant USC, pursuing its seventh straight Pac-10 title.
Arizona Stadium has become a dangerous destination for Top 25 teams. The Wildcats have knocked off six ranked teams in coach Mike Stoops' five seasons, including three in the Top 10.
Were it not for USC's defense, Arizona (5-2, 3-2) might have added the Trojans to their list of upset victims.
USC wouldn't give an inch -- literally. Late in the fourth quarter, Arizona quarterback Willie Tuitama tried to sneak on fourth-and-an inch near midfield, but the Trojans repelled him.
"Guys were out there saying, 'This will determine who we are,' " Maualuga said.
Arizona's offense had one more chance less than two minutes later. But that stop was pivotal.
"That's a big play, and we have to be able to get an inch," Arizona tight end Rob Gronkowski said.
Tuitama didn't fare much better in the pocket. With Trojans buzzing around him all night, the senior star completed 14 of 30 passes for 88 yards and threw an interception.
Arizona mustered only 188 yards, a good quarter for the Wildcats against lesser opponents. The potent Wildcats had averaged 40.4 points per game, ninth in the nation.
"I loved the way our guys played on defense tonight," USC coach Pete Carroll said. "I thought this was a really good, good night against a really big-time offense."
USC's offense was a different story. Mark Sanchez threw for 216 yards and a touchdown, but he also threw an interception and lost a fumble on a sack.
The Trojans' attack was reduced to Stafon Johnson left, right and up the middle.
The junior from Compton, Calif., ran for 83 yards and a touchdown for the Trojans.
"We were really riding on his shoulders," Carroll said. "He did a great job of carrying us."
Johnson's biggest play came on a play that he didn't touch the ball. He threw a block that enabled the Trojans to score the decisive touchdown.
The Wildcats had tied the game at 10-10 early in the third quarter, cashing in on a Sanchez fumble deep in USC territory.
Arizona defensive end Brooks Reed sacked Sanchez, forcing a fumble that was recovered by tackle Donald Horton at the USC 15. Four plays later, Nic Grigsby scored on a 5-yard run to tie it at 10-10.
The cardinal-clad crowd of 57,427 was rocking Arizona Stadium. But the Trojans calmly responded with a nine-play, 80-yard drive capped by a 30-yard touchdown pass from Sanchez to Stanley Havili.
The pass wouldn't have happened if it weren't for Johnson, who took out blitzing safety Nate Ness as he zeroed in on the passer.
"The name of the game is protecting the quarterback," Johnson said. "I didn't want to be accountable for a blitz that didn't get picked up."
Johnson said he didn't realize how big the block was until he saw a replay on the video board.
"Man, if I would have missed that, it would have been daylights," Johnson said.
Ness had to be helped off the field. That saddened Johnson, who said he and Ness "are like best of friends" and had been Pop Warner teammates as children.
Even with that lead, the Trojans needed a little luck in the waning minutes. On first-and-10 at USC's 3, Johnson fumbled at the 10. But USC tight end Anthony McCoy recovered and rumbled 29 yards to the 39.
"I was down," Johnson said, chuckling.
Of course, the Wildcats still would have had to score a touchdown to tie it -- a tall order against these Trojans.
"They were just too good defensively," Stoops said. "And that was really the story tonight."
"Against most teams, that would have went all the way," Stoops said. "Barkum is one of our fastest guys, but USC is so gifted athletically they were able to run him down."
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