NORMAN, Okla. (AP) -- Senior linebacker Corey Nelson doesn't sugarcoat it -- he thinks Oklahoma had a subpar season defensively in 2012, and he was as much to blame as anyone.
The numbers don't lie. The Sooners gave up an average of 398.3 yards per game, including 192.2 yards rushing -- and those the numbers grew worse as the season progressed, particularly as Oklahoma faced high-octane offenses.
On Nov. 17, West Virginia rolled up 778 yards (458 rushing, including 344 by Tavon Austin), then a week later Oklahoma State followed with a 618-yard offensive outing. Oklahoma managed to win both those games, but then Heisman Trophy-winning quarterback Johnny Manziel rushed for 229 yards and passed for 287 more as Texas A&M routed the Sooners 41-13 in the Cotton Bowl, part of a 663-yard effort by the Aggies.
"I feel like I have a lot to prove, since last year was a down year," Nelson said. "It's not even just me; it's just the defense as a whole. We all have something to prove. After last season, especially the last game, we have something to prove."
Playing in the Big 12, a conference in which so-called "tempo" systems are in vogue at places like Baylor, West Virginia, Oklahoma State and Texas Tech, defensive coordinator Mike Stoops knows there must be some changes made. Especially if the Sooners are to slow down opposing offenses enough so that Oklahoma's offense isn't continually forced to ride to the rescue, as happened several times last season when the Sooners finished 10-3.
Five Big 12 teams -- those four, plus Oklahoma, which also uses a tempo offense -- all ran 993 or more plays last season, all ranking in the top 13 in that category among Football Bowl Subdivision teams.
Stoops has talked during the preseason about the Sooners creating more confusion among opposing offenses, and Oklahoma defenders say that's been an emphasis as they prepare for their season opener Aug. 31 against Louisiana-Monroe. Junior defensive back Julian Wilson said it's a matter of "disguising everything" and that the Sooners' goal is to "basically, just play with the quarterback's head."
But against a tempo offense, which doesn't huddle and tries to snap the ball as quickly as possible in order to limit defensive substitution options, that's easier said than done. The Big 12 is adding an extra official this season, whose job is to spot the football as soon as possible after a play has ended -- a move that could speed up play even more. Wilson said it's important for Oklahoma defenders to be in shape.
It's "getting to the line, knowing your assignment," Wilson said. "OK, you know you're not coming? Bluff like you're coming, but you're really not."
Senior safety Gabe Lynn said he didn't understand just how fast some Big 12 offenses were until he took the field. He said it's key for Oklahoma's veterans to emphasize to newcomers that preparedness is key.
"I'm just trying to relay to them how important it is to get the call and get lined up," Lynn said. "Against tempo offenses, you have to be prepared and be ready to play."
Linebacker play will be critical, Stoops said, as they will need to be cover receivers in space in addition to trying to plug running lanes. Nelson thinks the Sooners are in good shape in that regard.
"It's all about speed," Nelson said. "You look at the Big 12; it's all about spread offenses and zone-read option, the quarterback throwing the ball all over the place. With linebackers like us in the Big 12, you've got to be able to run. That's one of the key components that we have at the linebacker position. All of our guys can run."
Stoops said success in the Big 12 will come down to "who can make the best adjustments, who can play the best and most consistent defense in this league." He said the Sooners must find a way to attack the run while remaining sound in the secondary.
"Hopefully we'll come up some different ideas than we did a year ago," he said. "I just thought we were too predictable a year ago."
Stoops rejected the notion that the definition of a great defense in the Big 12 needed to change.
"I think we know what great defense is," he said. "I know our players' expectations. Again, holding people to 17 points or 10 points in a game is just not realistic. Now, letting them run up and down the field for 700 yards, that's not realistic, either. . That's embarrassing. There's a balance in there. Again, we all made a lot of mistakes. Maybe we got lulled to sleep in the first eight weeks of the season."
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