Our Big 12 Week 6 power rankings:
1. TCU (previous ranking: 2): The Horned Frogs are in great position, as the league's only undefeated team at the moment following a 31-24 win over West Virginia. A tough road contest at Kansas State is up next.
2. Oklahoma (1): A 38-31 upset loss to Iowa State -- at home, to a walk-on reserve quarterback no less -- strikes a significant blow to the Sooners' playoff hopes. Games against Texas (Week 7), TCU, West Virginia and Oklahoma State still remain, meaning even a trip to the Big 12 title game is no guarantee at this point.