Inside the Box: USC's Defense Has Given Up Yards All Season Even Controlling for the Quality of Offense in the Pac-12

By Vico on December 28, 2017 at 1:30 pm
Oct 21, 2017; South Bend, IN, USA; Southern California Trojans safety C.J. Pollard (28) sits on the bench late in the 4th quarter in a loss to the Notre Dame Fighting Irish at Notre Dame Stadium. Mandatory Credit: Brian Spurlock-USA TODAY Sports
Brian Spurlock-USA TODAY Sports
9 Comments

USC has some advantages over Ohio State. Defense isn't one of them.

Analyses of the upcoming Cotton Bowl will invariably square on what might be the best player on either side of the field. Sam Darnold is potentially the No. 1 quarterback off the board in the 2018 NFL Draft. He's one of several marquee attractions from the best conference for quarterback play in college football. Ohio State will not have seen a player like him since Baker Mayfield in Week 2. That game did not go well.

That major difference-maker for USC stands in contrast with advantages Ohio State has elsewhere in this game. Sam Darnold's individual brilliance is observable despite some important limitations in USC's passing offense. USC's rushing offense might be more than just an ad hoc supplement to the offense. USC performs better as a team when its ground game can get going, which is not something we have reliably seen this year.

Further, USC's offense does most of the heavy-lifting for the team. The defense's best is mediocrity. Its worst efforts are eye-opening. Ohio State will have a major advantage over the USC on defense.

Here is a quick comparison of Ohio State's defense each game to USC's defense. The difference is clear. USC reliably conceded more yards in almost every game this season. USC conceded an average of 404.7 yards per contest to Ohio State's 292.3.

USC's Defense vs. Ohio State's Defense

The differences are even clearer after controlling for Ohio State's rough start to 2017. Ohio State's defense improved every game thereafter en route to finishing the regular season and championship games as the country's No. 8 total defense. The only game in which Ohio State conceded more yards on defense than USC conceded in a typical game was the Iowa loss.

The only superlative for USC's total defense relative to Ohio State's total defense, if you can call it a superlative, is the Trojans show less variation from game to game than Ohio State does. The standard deviation for Ohio State's total defense is 132.8 yards per game. That's more than twice USC's variation of 64.8.

However, that at best says USC could put up yards on Ohio State's defense with Sam Darnold at quarterback. It doesn't lend much optimism to hopes from Trojan fans that it could stop Ohio State's offense. It hasn't done that to any offense this year. Even Oregon State, the country's No. 114 total offense, put up more yards (319) on USC's defense than Penn State, the country's No. 27 total offense, put on Ohio State's defense.

USC's rushing defense in 2017

USC's rushing defense has been a problem at some inopportune moments this season. It conceded 263 rushing yards to Western Michigan in the season-opener, a major reason why the Broncos hung around as long as it did against USC in the Coliseum.

It also allowed 122 rushing yards to Washington State. On paper, this is a decent effort. Understanding that Washington State is the country's No. 129 rushing offense makes this look even worse. 122 rushing yards is an increase of 42.33% from Washington State's season average.

It's the worst game on the season for USC's rushing defense by that metric. It's worse than 39.5% increase for Notre Dame from its season average in the game on Oct. 21. However, let's not lose sight of how bad that Notre Dame loss was. The Irish hung 370 rushing yards on USC in that beatdown in South Bend.

USC's passing defense is somehow the bigger worry despite these statistics. The Trojans have the country's No. 97 passing defense.

USC's passing defense in 2017

We can qualify that the Pac-12 is a quarterback's league. The Big Ten, for example, doesn't have quarterbacks like Sam Darnold, Luke Falk, or Josh Rosen. However, take a look at the last two regular season games against Colorado and UCLA with that in mind.

Any discussion of the Pac-12 as a quarterback's league typically omits Colorado's Steven Montez. He's a fine quarterback but he would be nothing out of the ordinary if he were a quarterback in the Big Ten. He's the Pac-12's No. 6 quarterback on the country's No. 40 passing offense that won five games in 2017. That quarterback lit up USC for 376 passing yards, a full 128 passing yards more than Colorado's season average against Power Five teams.

The game against UCLA was also grisly for USC's secondary. Josh Rosen, arguably the best pure passing quarterback in college football, hung 421 yards on USC. That's not outside the norm for Rosen but it's a full 87 yards more than what UCLA typically does in a game against Power Five opponents.

All bode well for Ohio State's offense, which ranks No. 15 in rushing and No. 28 in passing. USC has a puncher's chance against Ohio State as an underdog because of Sam Darnold. However, Darnold will need to do the heavy lifting for a USC team whose defense has been mediocre at best.

9 Comments
View 9 Comments