Being ranked in September is great, but many teams have yet to truly be tested in the 2013 college football season and will eventually be bounced from the polls as they carry on through the year.
Florida entered the season with BCS aspirations, despite an extremely difficult SEC schedule. Now the Gators will have to move on without one of their leaders on each side of the ball, making a slide out of the rankings a definite possibility.
Meanwhile, one of the best teams in the nation from last season may prove to have a tougher rebuilding task than originally thought.
In the Big Ten, a number of teams are near the tail end of the current rankings, leaving at least one faced with an inevitable drop from the polls.
Finally, in the wide open Big 12, one team could be headed for a late-season skid that will see it out of the final rankings.
Note: All rankings based on the Week 5 AP Top 25.
Florida might end up as the best unranked team at season's end.
The Gators have talent, no doubt, but their schedule is frightening.
UF plays four teams currently ranked No. 12 or higher, three away from home. That could potentially leave the Gators, currently 2-1, with five losses in the regular season.
If that is the case, Florida will need an impressive bowl win to remain ranked after all is said and done.
The UF offense will have to move on without quarterback Jeff Driskel, who was lost for the year.
Also, the recent season-ending injury to Dominique Easley, who was having a stellar season, will seriously hurt the UF defense.
Notre Dame hasn't been particularly impressive so far this season and its lone loss so far to Michigan is looking worse, considering the poor play of the Wolverines of late.
ND has two tough contests upcoming against Oklahoma and Arizona State, followed by a rivalry tilt with USC.
To close out the season, the Irish will take on two more challenging foes in BYU and No. 5 Stanford.
Like Florida, Notre Dame's final ranking may hinge on its bowl result.
Until then, the Irish will need to pick up their play on offense.
Northwestern, Michigan and Wisconsin each sit near the back of the polls in the wide open Big Ten.
At least one of the three will likely finish on the outside looking in.
Wisconsin already has one loss, but has looked like the most complete team of the three.
The Wolverines have the most question marks, given their suspect play lately, but won't have to play Wisconsin.
With all that said, Northwestern seems like the most likely candidate to fall out of the Top 25, given their weak defense and overall toughest road.
NU will play each of the toughest teams in the conference: Wisconsin, Michigan, Nebraska, Michigan State and Ohio State.
Texas Tech picked up a big early season win over TCU to jump into the Top 25 and will have some room to climb over the next few weeks.
The Red Raiders will ease into Big 12 play against Kansas, Iowa State and West Virginia.
However, TTU's schedule will ratchet up late with Oklahoma, Oklahoma State, Kansas State, Baylor and Texas coming over its last five games.
A string of late losses could send the Red Raiders out of the rankings and hoping for a late bowl win to salvage a spot in the final polls.