Auburn defensive back Nick Ruffin celebrates with Daniel Thomas after scoring a touchdown against Louisiana-Monroe. (Michael Chang/Getty Images)

Cade Massey, a practice professor at the Wharton School, and Rufus Peabody, a Washington-based sports analyst, developed this ranking system for projecting future performance. Ratings represent a team’s predicted point differential against an average team on a neutral field. Current season statistics are adjusted for home field, opponent and game situation, blended with preseason expectations and weighted by their predictive ability.

As we hit the home stretch of the 2017 college football season, the SEC is the fulcrum of this year’s playoff bracket. This is a bit of a surprise, given how sedate the SEC race has been so far, and how many other teams are still in the playoff hunt. But Auburn’s late-season rise changed everything. Many wrote off the Tigers in mid-October after their second loss, but they always had a clear, if unlikely, path to the playoff. Their first big step came with last week’s drubbing of Georgia, but two even bigger steps remain: Alabama this weekend and then, should they win, a rematch against Georgia in the SEC championship game.

Auburn is entirely capable of knocking off Alabama. The Tigers have been in the top 10 in our predictive ratings all season, despite their losses, and we now have them all the way up to No. 3. More to the point, we make them a five-point home underdog Saturday, the fewest points Alabama has given all season.

Most important to everyone else in the country: If Alabama loses Saturday – or the following week – the SEC is more likely to claim two spots in the four-team playoff. Would a two-loss Big Ten champ Ohio State land one of the remaining two? How about a two-loss Big 12 champ TCU?? Alabama is clearly the best team in college football right now – and one loss likely won’t change that. But the committee is tough to forecast. Would they go with the better team? Or a conference champion deemed more “deserving”?

There are three ways the SEC can go over the next two weeks. Here’s how we see those scenarios playing out.

Scenario #1: Alabama beats Auburn and Georgia (Probability: 49 percent)

In the “boring” scenario, Alabama wins out. Our rating system has them as the nation’s best team, sporting the No. 1 defense and No. 4 offense. They will be favorites in both games – by five over Auburn on the road, and by eight or nine over Georgia in the championship game in Atlanta. If the chalk holds, Alabama would go into the playoff as the No. 1 seed and Georgia likely would be on the outside looking in, pulling for chaos.

Scenario #2: Auburn beats Alabama & Georgia (Probability: 22 percent)

Many are pulling for Auburn to win out if only because of how breathtakingly unlikely it seemed just a few weeks ago. But the Tigers seem to be peaking just as Alabama has been showing signs of wear.  According to our game grades, Alabama outperformed Auburn in eight of the season’s first nine weeks, but Auburn has trumped Alabama since. And if Auburn takes the Iron Bowl, we’d make them a slight favorite over Georgia in the SEC title game.

Auburn almost certainly makes the playoff (92 percent) if it wins out, but what about Alabama? This is one of the Tide’s worst scenarios because they could use the quality win over Auburn to burnish their case with the committee. Still, our model gives them an 83-percent chance of landing a playoff spot, depending heavily on how they lost to Auburn and what else happens around the country.

Scenario #3: Georgia beats the Alabama-Auburn winner (Probability: 29 percent)

Keen observers know a football team is never as good, or as bad, as it looked last week. Yet people tend to over-react, especially to something as colorful as Auburn’s pasting of Georgia. The Bulldogs are a better team than they looked in that game. They bounced back with a 42-13 win over Kentucky, the third-best performance of the week, and climbed two spots in our rankings to No. 5. They will be an underdog in the title game regardless of whom they play, but should benefit from playing in Atlanta.

Obviously a one-loss SEC champion Georgia would be in the playoff. And equally obvious, a three-loss Auburn would not be. The interesting question is what happens to Alabama in this scenario. They stand a stronger chance (90%) for a second SEC bid if they are the team Georgia beats in the title game, as they would have beaten Auburn on the way.  But we believe a one-loss Alabama team is still very likely to make the playoff regardless. What would be their path in? They’d need to displace the Pac-12 champ (a virtual certainty) plus another Power Five champion. We’re confident the committee wouldn’t slot a one-loss Alabama team over an undefeated Wisconsin or Miami, or one-loss Clemson, Georgia, or Oklahoma. But we do favor Alabama over Ohio State, which we project as having a 73-percent chance of winning the Big Ten, but whose 32-point loss to Iowa may be too much to overcome.

Our model shows a number of more remote possibilities that would provide Alabama avenues into the playoff. Wisconsin could lose to Minnesota, then go on to beat Ohio State for the Big Ten title (2.5-percent chance of this occurring). Georgia could lose to Georgia Tech before winning the SEC title game (5.5 percent). Clemson could lose to South Carolina, then beat Miami for the ACC title (7.8%), or Miami could lose to Pitt and win the ACC (4.4 percent). Plus, the eventual Big 12 champion could still lose its regular season finale (4.7 percent). None offer slam dunks for the Tide, but collectively they significantly bump up their chances.

In our mid-season review, posted just after Auburn took its second loss against LSU, we suggested the Tigers were still nationally relevant. But we didn’t quite expect them to do what they’ve done since. Can they keep it up? Whether or not they do, the SEC’s top three teams will hold the country’s attention the next two weeks.

— Bob Tedeschi contributed.

Team Scenario Conf
Likelihood In
Alabama 13-0 W 49% 100%
Miami 12-0 W 25% 100%
Wisconsin 13-0 W 24% 99%
Georgia 12-1 W 24% 99%
Clemson 12-1 W 63% 100%
Oklahoma 12-1 W 60% 96%
Alabama 12-1 L 15% 90%
Auburn 11-2 W 22% 92%
Miami 11-1 W 4% 94%
Alabama 11-1 36% 83%
Wisconsin 12-1 W 3% 71%
Georgia 11-2 W 6% 73%
Clemson 11-2 W 8% 75%
Miami 11-1 L 58% 31%
Ohio State 11-2 W 62% 36%
Oklahoma 11-2 W 4% 42%
TCU 11-2 W 36% 34%
Wisconsin 12-1 L 65% 15%