Fighting Irish Defense Is a Playoff Disruptor
NCAA Week 10 - Notre Dame dominated Clemson on Saturday night in a 35-14 victory spearheaded by big defensive and special teams plays, likely slamming the door shut on a potential berth for the Tigers (or anyone else in the ACC) in the College Football Playoff in the process. The previously undefeated Tigers had ranked fourth in the initial committee rankings release last week, but fell to 10th last night following the defeat, behind three other one-loss teams and two-loss Alabama. The 6-3 Irish entered the CFP rankings at No. 20 this week, outside of the national championship conversation and at the fringes of contention for a New Year's Six bowl game. But they have asserted themselves as a team with confidence and a defense-first identity for the stretch run.
The Notre Dame defense allowed Clemson to cross midfield only once in the first half of the game, a drive that stalled out at the Irish 38-yard line with a turnover on downs. The Tigers didn't have a drive reach the red zone until early in the fourth quarter, already trailing by 21 points, and that drive ended with an interception returned 96 yards for a touchdown by freshman cornerback Benjamin Morrison to seal a 28-0 Irish win in non-garbage time. Morrison's interception on the previous series deep in Clemson territory set up a short field touchdown drive for Notre Dame. That four-possession sequence (interception-touchdown-interception-return touchdown) put the game away with 14 points on the scoreboard, 10.9 of which were attributable to the defensive stops and returns generating the field position and scoring value.
Non-offensive value was the story of the game for the Irish. They blocked a punt after forcing Clemson's first offensive drive to lose yards and returned it for a score and a 7-0 lead. It was the sixth punt block of the season for Notre Dame, and the first touchdown for a unit that now ranks No. 1 in my punt return efficiency special teams metric. Punt return efficiency is calculated by measuring the resulting field position following a punt exchange with the expected field position based on where the punt is kicked. On average, the Irish have generated an extra 0.27 points of scoring value per opponent punt, the equivalent of 8 to 10 yards of field position per drive and a couple of points per game.
The Irish also rank No. 1 in net starting field position coming out of the Clemson game, starting their non-garbage drives on average from their own 34-yard line and forcing their opponents to start drives on average from their own 25-yard line. An average game features approximately 12 offensive possessions for each team, so a per-drive advantage of 9 yards is equivalent to having to move the ball on offense 108 fewer yards per game to the end zone. That's particularly useful for an offense that runs the ball well but has limited big-play potential. The Irish offense ranks No. 49 overall in this week's opponent-adjusted OFEI ratings and averages only 5.6 yards per play (79th nationally). Only 9% of Notre Dame's non-garbage drives this season have averaged at least 10 yards per play, 100th in FBS. They gashed Clemson on the ground with an 11-play, 78-yard scoring drive in the first half, but also had many other drives move effectively before stalling out just beyond or just short of midfield. Punts pinned the Tigers deep, and the Irish controlled the game script throughout, but only 0.6 points of Notre Dame's 28-point lead at the end of non-garbage time was ultimately credited to the offense.
It has been a bit of a perplexing season in South Bend. First-year head coach Marcus Freeman had one of the toughest opening assignments possible in a Week 1 road trip to Columbus, Ohio, against national championship contender Ohio State, a game in which the Irish threatened the Buckeyes deep into the second half before falling 21-10. They then laid an egg against Marshall (currently FEI No. 73) at home, but ripped off wins against North Carolina (No. 50) and BYU (No. 59) before tripping up inexplicably again against Stanford (No. 82). Preseason expectations had already been adjusted, but a 3-3 record with those clunkers presented the possibility of a disastrous finish. FEI regular-season win projections for Notre Dame bottomed out at 6.8 mean wins after the Stanford game, but have vaulted back up to 8.2 mean wins following the victories over UNLV (No. 101), Syracuse (No. 34), and Clemson (No. 21).
Irish fans are primed to carry the momentum from a big night and wild celebration forward, and might be lamenting what-if scenarios if they hadn't played so poorly against their worst opponents to date. But though the sequence of victories and defeats has been unusual, the Irish are pretty much exactly where a team with their offense and defensive efficiency metrics should be. A 6-3 record with losses to Syracuse and Clemson instead of Marshall and Stanford might have made more sense given the statistical profiles of those teams, but teams rarely show up in the same way week-in and week-out. And a team that has found its footing late in the year is well-positioned for the relatively modest tests that await. With a regular season finale against USC (FEI No. 13) after games against below-average Navy (No. 76) and Boston College (No. 102), my numbers project a 35% likelihood that Notre Dame will finish 9-3, and a 90% likelihood they'll be no worse than 8-4.
The USC game may present the opportunity for Notre Dame to kick another potential College Football Playoff contender out of the picture as well. Even if the Irish aren't in the title conversation themselves, their defense may have something to say about which teams are.
2022 FEI Ratings (through Week 10)
Fremeau Efficiency Index ratings (FEI) are opponent-adjusted possession efficiency data representing the per-possession scoring advantage a team would be expected to have on a neutral field against an average opponent. Offense ratings (OFEI) and defense ratings (DFEI) are opponent-adjusted drive efficiency data representing the per-drive scoring advantage a team unit would be expected to have against an average opponent unit. Net drive efficiency (NDE) is the sum of offensive drive efficiency and defensive drive efficiency data representing scoring value earned by offense and defense units per drive. Strength of schedule ratings represent the expected number of losses an elite team two standard deviations better than average would have against each team's schedule to date (ELS), the expected number of losses a good team one standard deviation above average would have against the schedule to date (GLS), and the expected number of losses an average team would have against the schedule to date (ALS). Ratings for all 131 teams are found here, and expanded ratings including projected win totals are found here.