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

COLUMBUS, Ohio — Ohio State defensive coordinator Jim Knowles agreed to a deal to serve the same position at Penn State. The Nittany Lions hired Knowles on Monday to replace Tom Allen, who left to take the same job with Clemson after Penn State fell to Notre Dame in the College Football Playoff semifinals.

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

It was the furthest thing from a happy ending between the newly minted Penn State defensive coordinator Jim Knowles and his former school.

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

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?

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.

After Michigan football ran, ran again, and ran some more against rival Ohio State in 2021, Ryan Day recognized that he needed to make something of a drastic change. Out was longtime OSU staffer Kerry Coombs as the defensive coordinator, and in was Oklahoma State DC 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.

Ryan Day checked off the big box of winning a National Championship earlier this month and became just the third active college football coach to do so. Day’s sixth season in Columbus is the one where it all came together and the Ohio State Buckeyes went on a magical run to win the College Football Playoff.

In hiring Jim Knowles, Penn State followed the adage: If you can't beat them, turn them to your side. While everyone in college football is already talking about Penn State's new defensive coordinator Jim Knowles, it's possible that not everyone is realizing how much his betrayal of Ohio State benefits his new club.