The Buffalo Bills are cleaning house, with new head coach Joe Brady set to build his own staff. Brady is an offensive-minded coach, having stayed on that side of the ball his entire career- the Bills need someone to run the defense.
The defensive coordinator search will weigh heavily, as it's the most important hire remaining. Who do they choose from, and why? Here are some of the top candidates on the market for Buffalo.
Defensive coordinator candidates Bills must look at
Jim Schwartz - Cleveland Browns defensive coordinator
Fans may have heard the news- Browns defensive coordinator, and former Bills DC, Jim Schwartz may call it quits with Cleveland. In a stunning move, Schwartz said his farewells and left the team, reportedly outraged by the organization's decision to overlook him for head coach. It's an unsurprising angle, and Schwartz will have to force his way out to hit the open market, but he will be highly-coveted.
Responsible for the lone good thing Cleveland has to offer, it's defense, Jim Schwartz is exceedingly qualified. In Buffalo, familiar territory, he would have his run of the defense. Returning to the Bills would give Schwartz the perfect platform for his head coach campaign; He's the ideal candidate to revolutionize the defense.
Jim Leonhard - Denver Broncos' defensive pass game coordinator/ ass. head coach
Of the coaches immediately available, Jim Leonhard is likely the most coveted. His time with the Broncos has been regarded as a smash hit, and his secondary philosophy has shut down innumerable talented quarterbacks and wide receivers. As a player, Leonhard spent four of his ten seasons on the Buffalo Bills, having started there as an undrafted free agent.
He has already interviewed with other teams like the Chargers for defensive coordinator positions, but the Bills are an attractive place to work. Joe Brady allegedly already has eyes for him, and it's understandable why.
The 43-year old is a younger coach, but one with plenty of experience on the turf and off it. His time as assistant head coach in Denver this season certainly adds to his resume, but it will be his ability to defend the pass with a clipboard that gets him on the staff.
Zach Orr - Baltimore Ravens defensive coordinator
Zach Orr is a solid candidate for the Bills' open defensive coordinator job, but there are plenty of teams interested. His success with the Ravens' defense these last two seasons is notable, and the respect his players have for him carries great weight.
One of the hottest names on the market, Orr may have his pick of teams. The problem is this: The former Ravens HC and OC, John Harbaugh and Todd Monken, are now the head coaches of the Giants and Browns- Both want to keep their recent colleague by their side. In order to secure Zach Orr, the Bills will need to make a very tempting offer.
Adam Fuller - Los Angeles Chargers safeties coach
A mixed bag, Adam Fuller has as much coaching experience as half this list put together. His 27 seasons with a clipboard indicate a wealth of knowledge. His 2025 season with the Chargers was his first in the NFL, but he has experience in numerous roles across this span, with a lot of play-calling thrown in. If the Buffalo Bills want a veteran behind a head coach as young as Joe Brady, Fuller is certainly the part.
He was a defensive coordinator back in 2004, and as recently as 2024. There is no question about qualification, but is he the right man for the job? Buffalo needed help at many levels on defense in 2025, and Fuller has the tools to succeed. His safety group in L.A. this season is a credit to the transferability of his skillset.