Familiarity breeds upsets in college football.
Oklahoma, Texas and UCF were upset by teams that they have struggled against historically in Week 5. Because of those results, they will be among the many programs tumbling down or dropping out of the Top 25 ahead of Week 6.
Pittsburgh, Mississippi State and Memphis also lost to unranked opponents, while Auburn and Texas A&M should drop a bit following losses to ranked SEC foes.
The top five in the college football polls is not expected to change since Clemson, Alabama, Florida and Georgia won in commanding fashion and Notre Dame did not play.