IRVING, Texas — Teams don’t wait until after the bowl game to look back on a season. Most of it is done when the regular season ends. The results of that analysis are important.

Oklahoma’s defense went through that internal autopsy before it ever left Norman for Friday’s AT&T Cotton Bowl Classic against Texas A&M.

Specifically, it has to come up with a better formula for stopping the run against spread offenses. The 911 yards it gave up in a three-game span against Oklahoma State, West Virginia and Baylor made the need for some alterations obvious.

“I think we’ve lived and learned from the past games,” OU middle linebacker Tom Wort said. “Some of the running quarterbacks we’ve faced — the quarterback draw especially — have created a huge problem for us. We’ve gone back and made the adjustments that give us the best chance to succeed.”

The Sooners better. As prolific as most of the offenses are in the Big 12 Conference, Texas A&M quarterback Johnny Manziel ran wild throughout the SEC en route to the Heisman Trophy. In terms of having to contain a running quarterback, Friday’s challenge will be the toughest the Big 12 has faced this season.

OU has remained vague on changes they’ve made. Defensive coordinator Mike Stoops likened it to solving riddles that have no answers.

“You take away the pass, you get hurt in the run. You take away the run and you get hurt in the pass. You want it both ways and it’s easy to say, but try to do it,” he said. “Everyone has all the answers, but they don’t understand all the problems. You can always take one thing away. If you try to take both away, that’s where the balance and understanding of weakness and strengths comes in. There’s a lot of stress put on defenses.”

There’s no doubt about that. Spread offenses were designed to easily identify defensive weaknesses and quickly exploit them. The Sooners have been dealing with them for several seasons.

The change Stoops made this season was tilting the defense toward stopping the pass in certain games. It matched any receiver with defensive backs and it did every thing it could to keep from getting beat deep.

In many respects, the decision produced positive results.

The Sooners led the Big 12 Conference in pass defense and were ranked second in scoring defense. There was, however, a cost: giving up 187.8 rushing yards per game in conference play. Many see the over reliance on defensive backs as the reason.

Wort and weakside linebacker Corey Nelson spent long stretches on the sideline with extra defensive backs taking their place.

Linebackers, who have been at the heart of stopping the run since the game was invented became situational players.

“That's a fair comment, I really do think that,” linebackers coach Tim Kish said. “Our thought process... We go in every week knowing that we want to stop the run, but you see these diverse pass offenses, these four-wides and five-wides. We tried to come up with some wrinkles this year. Again, it was what we thought was best at the time. Sometimes it was favorable to us. Others, it wasn't. We learned from it, and we've kind of come into a happy mix where we're at today. I think it will evolve a little more toward the linebackers this year.”

Perhaps that was the diagnosis as the Sooners looked back on the regular season. How they try to defend the Aggies will carry over to the 2013 season.

Manziel offers the best season-ending test OU can face. He presents the problem its defensive has struggled to solve. Coming up with the correct answer means a major boost heading into the next season. If not, it’s back to the drawing board.