The Buffalo Bills continue to shape their new-look coaching staff with a major defensive hire under rookie head coach Joe Brady.
The team is hiring Jim Leonhard, formerly the Denver Broncos assistant head coach and defensive pass game coordinator, as their new defensive coordinator, according to NFL Network Insider Ian Rapoport. Leonhard joins recently hired offensive coordinator Pete Carmichael Jr. as Brady’s top two coaching lieutenants.
Leonhard, 43, is a rising star in the coaching ranks. After a 10-year NFL career as a defensive back—including four seasons with the Bills starting in 2005 as an undrafted free-agent safety—he began his NFL coaching career with the Broncos as a defensive backs coach and pass game coordinator in 2024. He was promoted to assistant head coach in 2025 and helped guide Denver to the AFC Championship Game, which included a Divisional Round overtime win over Buffalo.
Now Leonhard will take on his first NFL defensive coordinator role, replacing Bobby Babich, who served as the Bills’ DC for the last two seasons. He will also fill the gap left by former head coach Sean McDermott, who had been heavily involved in the team’s defensive play-calling during his tenure.
Leonhard brings a wealth of experience from his college coaching days at Wisconsin, where he was the Badgers’ defensive coordinator from 2017-2022 and served as interim head coach in his final season. In Denver, he played a key role in the development of Patrick Surtain II, the 2024 AP NFL Defensive Player of the Year, while helping the Broncos rank second in total defense in 2025.
The Bills reportedly interviewed other candidates, including the Dallas Cowboys, Los Angeles Chargers, and New York Jets, but Leonhard is returning to Buffalo, tasked with building a defense capable of helping Brady reach Super Bowl aspirations in his first year as an NFL head coach.
