College Football Playoff race: Pac-12 falls, Cincinnati and Big Ten are rising

Week 5 was packed with opportunities for undefeated teams to further assert themselves in their respective conference races, including four games between two undefeated top-25 opponents, narrowing the pool of serious contenders in the College Football Playoff race.

Hello, Cincinnati. Farewell, Arkansas. Not even close, Ole Miss. The East Coast was awake for that implosion, Oregon.

No, one-loss teams aren't eliminated from consideration, but they're certainly playing from behind. Here's how it all changed the playoff picture with one month until the first ranking is revealed on Nov. 2.

Forget expansion, Alabama and Georgia are making this a two-team race

Alabama and Georgia can both make a case for No. 1. According to ESPN's Football Power Index, they are more than a touchdown better than any other FBS team. Nobody in the ACC comes close. Oklahoma, the highest-ranked team in the Big 12, is squeaking by unranked teams like West Virginia and Kansas State. With Oregon's loss to Stanford, there are no undefeated teams left in the Pac-12. The Big Ten has one-loss Ohio State, and four undefeated teams -- Michigan, Michigan State, Iowa and Penn State -- but none of them are playing at the level of Bama or Georgia.