Updated

After watching Kansas surrender at least 40 points six times in Big 12 play last season, coach Charlie Weis reached a couple of conclusions.

First, his base defense wasn't designed to stop high-octane Big 12 offenses. Second, he had to switch some personnel to keep opposing teams from using the spread to create mismatches.

"Everyone has three and four wide receivers out there and you can't match up base defense against four wide receivers and be competitive in this league," Weis said. "So many teams are not only running no huddle, but snapping the ball so fast."

To address the first issue, Kansas switched to a nickel defense as its base this season. The new formation gives the Jayhawks a fifth defensive back and a buck, which linebackers coach Clint Bowen called "a glorified defensive end more than he is a standup linebacker."

As for the other issue, Weis brought in three junior college transfers to start in the secondary. One of those starters, Cassius Sendish, began at nickel back before switching to safety to help shore up the only area of the secondary Weis felt was a weakness.

Last Saturday, Kansas (2-2, 0-1 Big 12) had its first chance to test its new defense in conference play. Texas Tech ran 100 plays, passed for 404 yards and thumped the Jayhawks 54-16 in front of a stunned home crowd.

Weis doesn't think the defense played as bad as the statistics indicate. The Jayhawks' offense struggled protecting the football and went three-and-out on three straight drives in the first half, and the Red Raiders turned short fields into 24 points.

"I don't think the pace was the problem," said Weis, whose team plays TCU on Saturday. "I think it was the volume of plays that became the bigger problem."

To prepare for the rapid-fire Big 12 offenses, Weis implemented a drill where one offense ran a play, and after the whistle blew a whole new offensive team set the ball and snapped it.

Often it happened within 12 seconds.

Frenetic, yes, but Weis believes the nickel maximizes his team's athleticism and will keep it from getting worn down. The fifth defensive back replaces the strong side linebacker and shoulders defensive back and linebacker responsibilities.

After all, the Big 12 was the second-fastest league in the country last year, with its teams averaging 73.8 plays per game. Of the Jayhawks' opponents, seven of them ran more plays against them than the national 71.5 average, with Baylor running a blistering 91 plays in its victory.

"The game is different, the game is faster paced," Kansas defensive coordinator Dave Campo said. "On defense in this league, you've got to learn how to survive."

It's not as if the Jayhawks can't blitz out of the nickel defense, either. Kansas already has improved its sack production, racking up 10 through four games after having 12 all of last year.

"Some of it is scheme and different packages that we've put in defensively have allowed us to get a little more pressure on the quarterback," defensive line coach Buddy Wyatt said. "Some of it is the guys that we're blitzing have a little bit more speed and athleticism."

Weis knows he'll need the nickel as long as he's at Kansas, and as long as Big 12 offenses continue playing at the current pace.

That might not always be the case, though. He's coached long enough to know how cyclical football can be.

"I think that what you'll find as you go forward," Weis said, "is that football is always evolving so right now that's a trend that a lot of teams, or high-powered teams, are doing and a few years from now, probably they won't be doing it."