Jim Leonhard lands his first NFL defensive coordinator job

Former Wisconsin football coach Jim Leonhard has been an assistant with the Denver Broncos for the last two seasons, and he has now landed his most prominent NFL job to date.

Leonhard is expected to be hired as the new defensive coordinator of the Buffalo Bills, ESPN's Adam Schefter reported on Sunday. The 43-year-old spent this past season as the assistant head coach and defensive pass game coordinator under Sean Payton in Denver.

Prior to landing with the Broncos in 2024, Leonhard coached at Illinois and Wisconsin. He was the defensive coordinator at Wisconsin for six seasons before being named interim head coach in 2022. Leonhard led his alma mater to a 4-3 record during his brief stint as head coach.

Jim Leonhard drew interest from several teams

Leonhard was a popular candidate among NFL teams that either need or needed new defensive coordinators heading into 2026. The former All-American safety interviewed with the Baltimore Ravens and Los Angeles Chargers before he was hired by Buffalo.

Leonhard has been widely respected among NFL teams and credited with helping to lead the Broncos to the postseason this year. Denver lost 10-7 to the New England Patriots in the AFC Championship Game, but they were without starting quarterback Bo Nix. Inexperienced backup quarterback Jarrett Stidham started in Nix's place against New England. The results were predictable, as the Broncos failed to consistently move the ball in inclement weather.

Bills are banking on a different kind of experience

Though he does not have any prior experience as a defensive coordinator in the NFL, Leonhard is a veteran in many ways. He played safety in the NFL for 10 seasons from 2005-2014. His professional playing career began when he signed with the Bills as an undrafted free agent.

The Bills struggled defensively late in the season and in the playoffs, which led to longtime head coach Sean McDermott being fired. Joe Brady, who is McDermott's replacement, is hoping Leonhard can help fix a defense that gave up 33 points in a 33-30 loss to Leonhard's Broncos in the divisional round of the playoffs.