It's that time of year again.
As we enter the sixth week of the college football season, there are a number of teams with impressive records who look primed to make runs toward BCS Bowl appearances.
Unfortunately, very few teams will achieve that reality by season's end.
Highly-touted teams with national championship aspirations will fall, and underdog teams will enjoy season-defining victories.
At this stage of the season, contenders will begin to emerge, but more importantly, pretenders will be exposed.
Here's a look at some of this weekend's games that will feature upsets, and leave perennial heavyweight teams wondering what went wrong.
No. 17 Oklahoma at Texas Tech
Coming off a disappointing loss to Kansas State two weeks ago, Oklahoma will be hungry to redeem themselves, but they'll be up against an undefeated, under-appreciated Texas Tech Raiders team that has, at least statistically, the nation's best defense.
Landry Jones has been relatively disappointing thus far in 2012, and though he has the skills and ability to bounce back from last weekend, the Red Raiders' defense won't give him enough room to operate.
The Red Raiders will pull off the upset, as Texas Tech's offense, currently averaging over 500 yards of total offense a game, will out-gun the Sooners and move into the top 25.
Prediction: Texas Tech 34, Oklahoma 27
No. 4 LSU at No. 10 Florida
The Tigers haven't looked vulnerable often this season, save for the 12-10 nail-biter against Auburn in Week 4, but they also haven't faced a team as well-rounded and talented as the Gators, who have had a surprisingly successful season thus far.
Quarterback Jeff Driskel has been impressive for the Gators all year long, and has led Florida up the rankings through the team's first four games.
Both defenses are among the nation's best heading into Saturday's game, but Florida will continue their Cinderella run, and take down the Tigers at home in Week 6.
Prediction: Florida 27, LSU 24
No. 21 Nebraska at No. 12 Ohio State
Heading into one of the weekend's big-ticket game against Nebraska, the Buckeyes are undefeated, and appear primed to march into the top 10 with a win on Saturday.
However, Ohio State looked beatable against Michigan State last weekend, and the team's offense sputtered at times when the Spartans got physical.
Nebraska, coming off a confidence-boosting win over Wisconsin last week, will be hungry to make up for their early-season loss to UCLA. If they can take down Urban Meyer's boys, they'll be back in the top 20 in no time.
Prediction: Nebraska 23, Ohio State 20