College Football Rankings Week 13: This Year's Biggest Busts, Big 12 Edition

When the Oklahoma Sooners and Oklahoma State Cowboys were upended last weekend, it was just the latest drama in the highly unpredictable Big 12 Conference.

With the regular season winding down, we're starting to finally separate the overachievers from the underachievers.

Some teams, such as Oklahoma, have been huge disappointments because they slipped in a couple games and didn't meet lofty expectations. Other teams are busts because they've failed to step up all season long.

Here is a look at the biggest disappointments in the Big 12.

Texas A&M Aggies

Texas A&M was ranked second in the 2011 Big 12 media preseason poll. Fast forward three months and the Aggies find themselves in sixth place and barely hanging on to a bowl bid.

They've had no trouble moving the football behind signal caller Ryan Tannehill and the rushing duo of Cyrus Gray and Christine Michael. Their defense hasn't been too bad, either. So what's the big deal?

They can't seem to win the close ballgames.

Four of the Aggies five losses have been by four points or fewer, the most painful one being the quadruple-overtime loss to Kansas State two weeks ago. Ultimately, their failure to hold off opponents during crunch time kept them from being in the conference title hunt.

Oklahoma Sooners

It sounds weird to call an 8-2 team a bust, but that's what the 2011 Oklahoma Sooners are. Ranked first in the country in all the major preseason polls, Bob Stoops' squad has tripped up a couple times and will fall short of its BCS Championship goal.

The defense, particularly the secondary, has been exposed several times this season. The cornerbacks were outplayed in the loss to Texas Tech and the safeties have been vulnerable all season.

Oftentimes, the prolific offense led by Landry Jones was plenty enough fuel for Oklahoma to cruise to victory. But whenever the Sooners got into a shootout and the defense was tested by a legitimate air attack, they crumbled. It was a disappointing year for a defense that had four players who were on the preseason All-Big 12 defense team.

Texas Tech Red Raiders

Nobody expected Texas Tech to win the Big 12 heading into this season, but a 2-6 conference record is not what Tommy Tuberville had in mind for his club.

Seth Doege and the passing game have been fantastic all year, but nearly everything else has been dreadful. The Red Raiders have given up an average of 43.5 points in their conference games. Their inability to execute against the run has doomed them on almost every drive. Also, the defense has struggled to force turnovers, as Texas Tech is last in the Big 12 in turnover margin.

Their triumph in the slugfest against Oklahoma was their lone quality win of the season. All of Tech's other games against ranked opponents have ended in defeat.

In fact, in the four games since the Oklahoma game, the Red Raiders have been outscored 190-53. They had better hope next year's defense isn't as porous.

Baylor's Defense

The Baylor Bears' season definitely hasn't been a bust, especially not after their scintillating win over Oklahoma and Robert Griffin III chasing the Hiesman Trophy. But their defense has been one big letdown.

As a whole, Baylor has exceeded preseason expectations this season. Unfortunately, the defense is worse than expected and has kept them from achieving elite status in the Big 12 and BCS title chase.

The pass rush has been mediocre and the entire defensive unit has yielded loads of yardage on the ground and through the air. Against Big 12 opponents, the Baylor defense has been giving up 40.4 points per game. Giving up 30 points to cellar-dweller Kansas two weeks ago tells you exactly how poor this group is.

Texas' Offense

Mack Brown's Texas Longhorns have a 3-4 conference record, and the most painful losses have been the recent ones. The defense has held up their end of the bargain, but the offense has failed them in a couple of low-scoring contests the last two weeks.

Whether it's David Ash or Case McCoy under center, the Longhorns have struggled offensively when facing quality opponents. Texas is averaging 15 points per game against teams in the upper half of the Big 12.

They've been unable to move the chains and sustain drives; last week, for example, they went 4-for-16 on third downs against Kansas State. It's no surprise, then, that they've only scored one touchdown in their last two games.

Unless Texas finds a consistent passing game to balance out the running attack, they'll have trouble finishing out the season against Texas A&M and Baylor.