As impressive and improbable as the rise to No. 1 has been for the Notre Dame Fighting Irish, it could all be derailed Saturday with an upset in the Los Angeles Coliseum at the hands of the rival USC Trojans.
Lane Kiffin's team opened the season as the top-ranked team in the country, but has fallen drastically short of expectations, losing four games in 2012. But the Trojans would like nothing more than to play spoiler to Notre Dame's national championship aspirations, and they definitely have the talent in the fold to pull it off.
Here are keys to the Trojans abruptly thwarting the Irish's storybook undefeated season.
Throw early and often
CB Bennett Jackson is a ball hawk, leading the Irish secondary with four interceptions. Phenomenal All-American linebacker Manti Te'o has used his instincts to pluck six passes out of the air.
But as long as QB Max Wittek can avoid careless throws over the middle and take advantages of the side of the field that Jackson isn't on, the Trojans have a chance to be successful in the passing game. Notre Dame's run defense is simply too good, and Wittek will have to keep the defense honest and prevent the Irish from cluttering the box.
At his disposal is arguably the best athlete in college football, super sophomore Marqise Lee, as well as the always reliable WR Robert Woods. And if Wittek dares to go over the middle or down the seam, he may be able to find success by throwing to big tight end Xavier Grimble, who should pose some matchup problems.
Earlier in the week, Wittek was the one who guaranteed a victory over the Trojans' bitter rivals. He'll have a home crowd and a talented supporting cast to back him up, but RBs Silas Redd and Curtis McNeal won't be able to chew up yardage on the ground without first establishing the pass.
Leave it up to Everett Golson
The Notre Dame QB situation has been volatile despite the undefeated record, and Golson's lack of experience has, at times, been at the epicenter of the controversy.
Constantly fluctuating in and out of the lineup, the redshirt freshman has finally settled in under center. But this is easily the biggest game of his life, and it remains to be seen how he will react to the pressure of a nearly guaranteed national championship appearance on the line.
With a Trojans defense that has forced opponents into 18 interceptions, it's possible that Golson could make some mental blunders and gift the rivals with a pick or two.
Also working against him is the pro-Trojan crowd, although it is worth pointing out that he played some of his best football in Norman facing the Oklahoma Sooners.
But the pressure of this game is much more massive, and Golson typically has a stellar running game to rely on. If the Trojans can simply stuff the box and force the Irish quarterback to beat them, they have a great chance of making this game much more competitive.
Win the turnover battle
This seems like an obvious facet that the Trojans must excel in, but it is well worth emphasizing in the context of this team.
USC ranks tied for sixth with LSU with 29 turnovers forced (h/t NCAA.com). But the Trojans have given away the ball the same amount of times, which is tied for 112th in the nation. QB Matt Barkley threw two interceptions in each of the team's four losses.
Wittek has some sizable shoes to fill for this week and perceptibly beyond, when Barkley has graduated. The best thing he can do is to be aggressive, but not to a fault.
It will be his first start, and in the context of his guaranteed victory, he will be eager to prove himself. That said, the Trojans must be smart with the football and play an extremely disciplined game.
As leaky as the USC defense has been, Monte Kiffin's unit has clearly shown an ability to make plays. Look for an aggressive scheme and bump-and-run coverage on Notre Dame's receivers to press the issue and rally the home fans behind the underdog Trojans.