NCAA Football question?

The Longhorns, the sooners and the red raiders have a three way tie in the BCS rankings. The longhorns beat the sooners and the sooners beat the red raiders but the red raiders beat the longhorns. but people were saying that if the sooners win, they will leap over the longhorns in the rankings. What i dont get is that how will the sooners jump the longhorns if the longhorns beat them in a head to head match. And if the sooners were to leap the longhorns how would that happen if the sooners struggled and almost lost against the cowboys? and even the red raiders struggled and almost lost to the bears