As recently as October 16, Iowa was the No. 2 team in the country and was one of the four teams projected to reach the College Football Playoff. Then the Hawkeyes were upset by Purdue at home and consequently find themselves ranked No. 11 and needing a lot of help to get into the CFP.
That's how quickly things can change in the college football world, especially at the top. One loss is enough to knock a team out of College Football Playoff contention, especially if it comes in a game it was expected to win handily.