How does No. 13 Notre Dame beat rival USC? By following these four keys to the game.

These keys to the game will likely decide if No. 13 Notre Dame (5-1) can beat Southern California (3-3) on Saturday in Notre Dame Stadium (7:30 p.m. EDT on NBC).

Lock down London 

The Trojans like getting the ball to wide receiver Drake London. So much so that USC’s most important offensive weapon entered the week ranked second in the FBS in receptions per game (10.7) and receiving yards per game (138.7). London’s averages in both categories are higher than any individual season-highs on Notre Dame’s roster. 

The Irish must find a way to restrict London’s effectiveness. Limiting his catch total might be tough, but if Notre Dame’s secondary can prevent him from picking up many yards after the catch, that would be a victory. If London’s final stat line looks like Purdue’s David Bell against Notre Dame (seven catches for 64 yards), defensive coordinator Marcus Freeman should be thrilled.

Throw for it 

USC’s defense doesn’t rush the passer well. The Trojans have accumulated just 10 sacks in six games for an average of 1.67, which ranks No. 101 in the FBS. Opposing quarterbacks have been able to pick apart USC’s secondary as a result. The Trojans rank No. 110 in passing efficiency defense for allowing opponents to complete 64.1% of their passes with 12 touchdowns and seven interceptions. 

Regardless of whether Jack Coan or Tyler Buchner is in the game at quarterback for Notre Dame, the Irish should be able to find success through the air. The return of tight end Michael Mayer to the lineup should make their jobs easier. Maybe wide receiver Braden Lenzy, who had a breakout performance against the Trojans in 2019, can rediscover some of that playmaking ability too. 

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Protect the football 

Notre Dame managed to escape Virginia Tech with a 32-29 victory despite Buchner throwing a pair of interceptions. Those turnovers continued a trend for Notre Dame, which started the week prior with three turnovers given away in a 24-13 loss to Cincinnati. 

The Irish can’t afford to lose the turnover margin against a USC offense with the ability to make them pay for it. Coan and Buchner can’t be careless with the football. Running backs Kyren Williams and Chris Tyree need to keep it secure on offense and make sure to secure it on punt and kickoff returns, respectively. 

Embrace the elements 

Football weather is in the forecast for South Bend on Saturday. With temperatures expected to drop into the 40s, the Trojans will be greeted by a Midwest chill. The fall weather that hadn’t quite arrived in the area until this week should be perfectly timed for the visitors from Los Angeles. 

The Trojans already have enough complaints to deal with this season. Head coach Clay Helton was fired. Interim coach Donte Williams hasn’t exactly been leading an inspired team with a 2-2 record on his watch. A certain toughness should be required to beat the Irish in Notre Dame Stadium on Saturday. There’s little reason to believe this USC team can match Notre Dame's intensity if the Irish bring it.

Follow ND Insider Tyler James on Twitter: @TJamesNDI.