Defensively the Sooners have always been solid. Mike Stoops has reintegrated his brother Mark as the defensive coordinator following a failed attempt at head coaching in the desert of Arizona. That means the departure of Brent Venables who was a potential head coaching candidate in the minds of some Jayhawk fans a year ago. The Sooners consistently recruit at a level that provides the talent to compete with anyone on the defensive side of the ball. They have some weaknesses this year and but they are still a very solid unit.
Jefferson plays out of the free safety position, Harris plays out of the strong safety slot for the Sooners. These two head up one of the better defensive secondaries in the Big 12 and the nation. What makes this group more impressive is that they are equally effective at attacking the line of scrimmage in run support as they are at turning away opposing passing attacks. Jefferson leads the team in tackles, Harris checks in at no. 2. Both players have combined for 3 ints. The Sooners don't necessarily create a ton of takeaways, but they're decent in that department and it starts with the secondary.
Moving on to the corners and another solid pair of defensive backs for the Sooners. Colvin is third on the team in tackles with six pass breakups and two interceptions while Hurst is not to far behind. Harris and Jefferson probably set the tone for this group but Colvin and Hurst are right there with them in terms of production and ability. This will be a big test for the entire Kansas offense as this is probably the best secondary since Kansas State that the Jayhawks have faced.
Lynn is your guy when the Sooners go Nickel, Ibiloye is the added OLB if they go with a more traditional base set. Nelson leads this group in tackles but Wort is a familiar name that has produced for the Sooners in the past. As a whole this group hasn't been great for the Sooners and that has led to some gradual changes including more playing time for Frank Shannon. In general this is a group that Kansas can hope to run against, the bigger concern will be the front four and the safeties in run support.
McFarland is about the only one in this group who has had a steady position and that's because everyone else is so versatile. Oklahoma really does have a very solid rotation up front and they can throw a lot of looks at you with just a handfull of players. They can go bigger in run support, they can go small to get more speed on the field. This has always been an area where Oklahoma has done well and the Kansas offensive line will have it's hands full as they try to give James Sims some running room. This group isn't invincible, and Sims could have a decent game, but it's going to take a consistently solid effort from the Kansas offensive line.