Georgia assumed the No. 1 spot in the SP+ rankings four weeks into the 2021 season, briefly ceded it to a torrid Ohio State - more specifically, a torrid Ohio State offense - midway through the year, then pulled away from the field late in the year. The Dawgs couldn't reach the finish line 15-0, but they were still the class of college football, and they finish the year as both the national champions and the top-ranked team in SP+.
What is SP+? In a single sentence, it's a tempo- and opponent-adjusted measure of college football efficiency. I created the system at Football Outsiders in 2008, and as my experience with both college football and its stats has grown, I have made quite a few tweaks to the system.
It is, as always, important to note that SP+ is intended to be predictive and forward-facing. It is not a résumé ranking that gives credit for big wins or particularly brave scheduling -- no good predictive system is. It is simply a measure of the most sustainable and predictable aspects of football. If you're lucky or unimpressive in a win, your rating will probably fall. If you're strong and unlucky in a loss, it will probably rise. It is a look at how teams should likely perform moving forward.
A few teams managed to make one final move up the rankings (or face-plant down them) during bowl season.
Largest jumps
Six teams moved up at least seven spots:
Texas Tech: up 14 spots from 54th to 40th
Liberty: up 11 spots from 60th to 49th
Georgia State: up nine spots from 80th to 71st
Maryland: up eight spots from 68th to 60th
Michigan State: up seven spots from 35th to 28th
Western Michigan: up seven spots from 83rd to 76th
Texas Tech completed an odd season with a brilliant Liberty Bowl performance against Mississippi State and former Red Raiders head coach Mike Leach. In the end, they pulled off something unique: They finished 30 spots higher than their preseason projections ... while firing their head coach.
Largest stumbles
Five teams, meanwhile, moved down at least seven spots:
North Carolina: down 13 spots from 46th to 59th
Mississippi State: down 10 spots from 24th to 34th
Oregon: down 10 spots from 28th to 38th
Virginia Tech: down eight spots from 62nd to 70th
Marshall: down seven spots from 44th to 51st
What a disappointing season for Mack Brown and North Carolina. Projected 11th in the preseason, the Tar Heels showed enough upside to still rank ninth despite a 3-2 start, but they finished October at 22nd, finished November at 47th and then no-showed for much of a 38-21 Mayo Bowl loss to a South Carolina team that came into the game ranked 69th.
Conference rankings
We almost certainly overreact to what we see from conferences in bowl season, judging them by how half the conference performed in games with opt-outs, long layoffs, etc. Bowls are only going to tell us so much. Still, they give us one final, interconference data point for the season, and that does cause some movement in the averages.
Here are the average SP+ ratings, per conference, for 2021:
1. SEC: 11.6 (down 0.5 points from before the bowls)
2. Big Ten: 9.5 (+0.0)
3. Big 12: 7.8 (+1.3)
4. ACC: 6.1 (-1.0)
5. Pac-12: 2.6 (-0.8)
6. AAC: 0.9 (+0.3)
7. MWC: 0.1 (+0.1)
8. Sun Belt: -4.9 (+0.2)
9. Conference USA: -5.3 (+0.2)
10. MAC: -6.8 (-0.2)
The ACC and Pac-12 managed to each fall by about a point per team, which is impressive considering the small samples involved, while the Big 12, with its two New Year's Six bowl wins and 5-2 overall record, managed to rise by a similar amount. (The future Big 12, without Oklahoma and Texas but with Cincinnati, BYU, UCF and Houston, actually averaged a higher rating, at 8.2. That's pretty great.)
Maybe the most noteworthy average above -- besides the future Big 12's, anyway -- is that of the Mountain West. It ever so slightly managed to average a positive rating for the first time since 2007, when now-former conference members BYU and Utah both landed in the top 40 and no one finished below 97th.
This version of the MWC didn't quite have the depth of the 2007 edition -- UNLV and New Mexico finished 115th and 120th, respectively -- but it did have DEFENSE. The MWC's average defensive SP+ rating was 25.5, fourth overall and better than both the ACC (26.0) and Pac-12 (27.3, which was also below the AAC).
What makes the MWC's performance this season even more impressive is how far the conference rose compared to last year.
The SEC had similar ratings among its top four or so teams this year and still had Vanderbilt anchoring the averages quite a bit, but after featuring five teams with an SP+ rating lower than 3.0 last season, it had only one this year. The middle class improved enough (despite some shaky bowl performances) to give it a boost this year. Conference USA, meanwhile, managed four top-60 teams this year (including a surging WKU), compared to two last season.
Then there was the Pac-12. Woof. USC and Washington both crumbled from preseason top 15 to outside the top 80, Oregon managed to fall from 19th to 28th to 38th in its last two games, and only one team finished in the top 25. The conference as a whole returned as much of its 2020 production as just about anyone and laid a 2021 egg.
