It appears that Knowles didn't take long to shuck his scarlet red colors and put on the blue and white at Penn State, taking aim at the conference leaders. It's a huge get for Penn State, who already had one of the most productive defenses in the nation last year, and now adds arguably the top defensive coordinator in the sport to the mix in 2025.

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

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.

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

The departure of defensive coordinator Jim Knowles adds a challenge for Ohio State, which was already dealing with heavy roster turnover on defense.

The Ohio State Buckeyes capped off a great season with a historic College Football Playoff National Championship win, but defensive coordinator Jim Knowles found himself elsewhere for the celebration.

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.

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

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.

One of the coaches that helped lead Ohio State to its 2024 national championship is reportedly heading to a Big Ten rival. Buckeyes defensive coordinator Jim Knowles is set to take the same position at Penn State,

Ohio State star safety Caleb Downs gave his reaction on Monday to the departure of defensive coordinator Jim Knowles, who left for Penn State.