Sun Bowl preview: Dissecting Stanford’s struggles with pass-happy teams like North Carolina

When No. 18 Stanford and North Carolina meet in El Paso, Texas for the Sun Bowl, it will mark a contest between two teams that fell short of expectations in 2016.

But what makes an apparently disappointing consolation game for both sides intriguing is that the two teams’ styles could not clash more on the field, and in recent years, off it. Yes, I’m talking about that Rosa Parks essay.

Antics and NCAA violations aside, the Tar Heels’ offensive imbalance, sporting likely first-round pick in junior quarterback Mitch Trubisky but also the 99th best rushing attack in the nation, is in stark contrast with the Cardinal’s ground-heavy attack.

In his first full season as a starter, Trubisky completed 68.9 percent of his passes and threw 28 touchdowns to just 4 interceptions. Those efforts were good for the fourth-highest total QBR in the nation, topped by only the likes of Heisman-Trophy level talent like Baker Mayfield, Sam Darnold, and Lamar Jackson.

Despite UNC’s dominance of the airways, their rushing attack supporting Trubisky ranked just 99th in the nation. Once more, junior running back and the team’s rushing leader, Elijah Hood, will be absent from the backfield due to injury, leaving the Tar Heels thin on depth behind senior running back T.J. Logan.

The Tar Heels aren’t necessarily inept at running the football -- they rushed for 4.9 yards per carry this season -- but instead leaned heavily on Trubisky’s right shoulder.

In the pass-crazed Pac-12 Conference, Stanford has seen several teams with this type of imbalanced offensive profile. So one might think that the Cardinal’s experience against these sorts of teams would lead to elevated success, right?

Wrong.

As the data has shown, when Stanford plays pass-heavy teams (national rushing rankings 25 or more slots lower than their passing rankings), they fare worse than they do against more balanced or run-heavy teams.

Because 2015’s team was so much better than this season’s, I only included data from 2014 and 2016 in the samples, since they fit similar profiles. In those two years, Stanford struggled at times on offense due to up-and-down quarterback and offensive line play, while maintaining a strong defense, although 2016’s wasn’t quite at the same level. Stanford’s stronger offense in 2016 can be seen as balancing this factor out.

Given Stanford’s late-season surge in 2016, it seems fair to argue that these two teams were similarly talented.

In those two seasons, Stanford went 7-4 (.637) against teams that fit the Tar Heels’ pass-heavy profile, but finished 9-4 (.692) against teams that had more balanced production. That might not seem like a significant difference, until you consider the quality of teams similar and dissimilar to the Tar Heels.

The best pass-happy team Stanford beat was 2014’s Arizona State squad, No. 24 in FPI, but outside of that win, they didn’t top any team ranked higher than No. 36. The average FPI of a team they beat: 50.57.

On the other hand, Stanford took care of business against teams that didn’t rely so heavily on the passing game. The Cardinal picked up two top-eleven FPI wins in those two years, and fell only to No. 1 Oregon, No. 4 Washington, No. 14 Colorado, and No. 27 Utah.

Furthermore, despite similar opponents’ FPI ratings, Stanford’s average margin was more than half a point higher against balanced teams.

Although this is admittedly an inexact science given the small sample size, Stanford has generally proven to be more vulnerable against pass-heavy teams, especially those with a strong vertical pass game.

How can Stanford counteract this trend? Some might point to establishing the running game, a task not made any easier with junior running back Christian McCaffrey’s decision to sit out the game to prepare for the NFL Draft and avoid a catastrophic injury.

Stanford will fill the void with true sophomore running back Bryce Love, who certainly seems up to the task. In his lone start filling in for McCaffrey in 2016, Love racked up 129 yards on 23 carries in a 17-10 win against Notre Dame, a game in which Stanford was plagued by penalties, turnovers, and poor offensive line play.

At 5-foot-10, 187 pounds, Love isn’t the most physically imposing runner. But he certainly has the speed and skills to be a three-down back for the Cardinal, which has traditionally employed bruisers like Toby Gerhart in its power running offense.

"He's an every down back," Stanford head coach David Shaw told Palo Alto Online. "He's a physical, explosive runner. He's not a small back by any stretch of the imagination. He runs through tackles and he's tough. For a guy who's under six foot, he can push the pile and drive his legs."

This isn’t mere “coach-speak” -- Love can really bring it inside the tackles. Against Notre Dame, he averaged more than two yards per carry better inside the tackles than outside — 6.43 YPC inside (14 rushes, 90 yards) as compared to 4.3 YPC outside (nine rushes, 39 yards).

Running between the tackles, the hallmark of Stanford’s offense, Love thrives on his instincts, vision, and improvisation skills. If there isn’t a hole open, he’ll either wait for one to open or create his own by slipping through small holes or bouncing outside. The elusive Love has a knack for avoiding contact and creating space for himself to run, which allows his size to play up.

With his the drop-off from McCaffrey, the 2015 Heisman Trophy winner runner-up, to Love, shouldn’t be too steep. Expect a heavy doses of Love carries — that’s been the game-plan against North Carolina all year long.

Excluding bowl games, opposing teams have taken the most carries in the nation against the Tar Heels, and more than 150 more than any other team in the ACC, leaving North Carolina 113th in the nation in total rushing defense. Only in four games this season did opposing teams pound the rock fewer than 50 times against UNC. With so many opportunities to run power, you know David Shaw has been salivating over this game for weeks.

In spite of their trends against pass-heavy teams, if Stanford can take advantage of North Carolina’s porous front seven, it could be a very long day for the Tar Heels. With an established run game, improving junior quarterback Keller Chryst, who has posted a 89.1 QBR in his last three games, could take advantage on play-action.

Given the quality (or lack thereof) in the opponents’ defenses Chryst has faced as of late, it’s important to take his numbers with a grain of salt. But the Cardinal is undefeated in his five starts so far this season, a sign that Shaw made the correct choice in benching senior Ryan Burns in favor of Chryst.

With Chryst under center and Love in the backfield, Stanford hopes they can buck their apparent struggles against pass-heavy teams — the same way they always have. Fighting imbalance with balance.