As Ryan Day looks to hire his fourth defensive coordinator in seven seasons, here are potential candidates to replace Jim Knowles.

Just as Ohio State was celebrating its national championship victory at Ohio Stadium on Sunday, news broke that Jim Knowles was heading to Penn State.

Spirits were high in Columbus over the weekend as fans continued to celebrate the national championship win over the Notre Dame Fighting Irish from a few days before. Until Sunday afternoon. Then some rain dumped on the Buckeyes' championship parade,

Ryan Day is once again dealing with the consequences of success in college football after leading Ohio State to a national championship.

Penn State has lured Tom Knowles away from Ohio State. The Nittany Lions have hired Knowles to serve as their defensive coordinator.

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However, Knowles wasn’t in attendance. About an hour later, reports surfaced that Knowles is leaving Ohio State to serve as Penn State’s next defensive coordinator. The move leaves Day searching for a replacement. Here’s who he might consider as he enters his seventh season as the Buckeyes' head coach.

Just days after leading Ohio State's defense to a College Football Playoff national championship, Jim Knowles accepted a massive offer from Penn State. Where will Ryan Day look for his successor?

Penn State made the hiring of new defensive coordinator Jim Knowles official on Monday. Here's what each had to say about the move

Knowles will make Penn State's defense one of the best in the country, but his addition might help the offense too.

COLUMBUS, Ohio — Ohio State football is doing its part to retain defensive coordinator Jim Knowles. The Buckeyes have made Knowles an offer that would make him the highest-paid defensive coordinator in college football, according to multiple reports.