The Bills are bringing back one of their own to run the defense. Buffalo announced Saturday that it has hired Broncos defensive passing game coordinator Jim Leonhard as the new defensive coordinator.
Leonhard began his 10-year NFL career as a safety with the Bills (2005-07), signing with the team as an undrafted free agent. He went on to play for the Ravens, Jets, Broncos and Saints before returning to Buffalo in 2013. Prior to his time in the NFL, he played collegiate as the University of Wisconsin (2001-04)
Not long after his playing career, Leonhard made the jump to the coaching ranks, returning to his alma mater. He began as the Wisconsin defensive backs coach in 2016 then was promoted a year later to defensive coordinator for the next five seasons. In Leonhard's five seasons as defensive coordinator, UW has ranked among the nation's top five in total defense and top 10 in scoring defense four times.
Leonhard started his NFL coaching experience in 2024 with the Denver Broncos as the defensive backs coach & pass game coordinator. He was promoted to assistant head coach going into the 2025 season.
In two seasons with the Broncos, Denver's ranked third in yards allowed per game, third in EPA per pass attempt, third in passing touchdowns allowed and second in yards allowed per pass attempt.
Denver also ranked as one of the best third down defense's in the league the last two years, allowing a 35.5% conversion ranked (t-4th).
Leonhard officially rounds out Buffalo's coordinators on the coaching staff, joining offensive coordinator Pete Carmichael and special teams coordinator Jeff Rodgers.
