Kansas State was the Big 12 Champion. They were 11-2 (with the OSU loss that makes 3, but we'll say 4 because that makes his case better). Coming into the game and had just beat #1 Oklahoma 35-7 the game before they played the Buckeyes.
Notre Dame was 9-2 coming into the game with their only losses being an OT loss by 3 to Michigan State and the 3 point "Bush Push" loss to USC. They were 6 points from being undefeated. That was the best Notre Dame team in recent memory and deserved to be in a BCS game.