For two years in a row, a shaky defense has been the biggest obstacle between the Ohio State Buckeyes and a national championship. Now, head coach Ryan Day has taken a dramatic step to change that by bringing in former Oklahoma State defensive coordinator Jim Knowles.

So how will Knowles be able to work with the Buckeyes' existing personnel, and what is he going to do differently from the current staff?

Buckeye Scoop's Xs and Os guru Ross Fulton joins host Tom Orr to break down Knowles scheme, how he deploys his personnel, and how he makes things simple for the defense, but difficult for opposing offenses.