​There’s still a great deal of uncertainty surrounding the Buffalo Bills in 2026, especially on the defensive side. Even within that uncertainty, the way some observers view new Bills defensive coordinator Jim Leonhard’s plan to deploy a pressure-heavy, attack-focused unit may not unfold as expected. The reasoning behind that hesitation is likely twofold. It could simply take time for things to click in Leonhard’s first year with the coaching staff. There’s a need to educate holdovers from Sean McDermott’s regime while also integrating newcomers from free agency and the players selected in the 2026 NFL Draft.
Despite so much still up in the air, the loudest question right now is what Buffalo’s defense will look like in the upcoming season. It’s a reasonable inquiry, marking the first major organizational shift on that side of the ball in nearly a decade. It’s also fair to question what Leonhard, a first-time NFL defensive coordinator, will bring to the table.
Before joining the Bills, Leonhard served in roles including assistant head coach, defensive backs coach, and passing game coordinator during the 2024 and 2025 NFL seasons with the Denver Broncos. However, he had not been tasked with calling Denver’s defense. The last time Leonhard called a defensive scheme was in 2022 when he served as Wisconsin’s defensive coordinator. It’s here that NFL writer and analyst Doug Farrar sought to uncover what Leonhard might contribute to Buffalo, sharing his findings with Chris Brown and Steve Tasker on a recent segment of “One Bills Live.” The take offered some intriguing perspective.
Yes, Leonhard has never called an NFL defense and hasn’t held the role of professional-level defensive coordinator, and he hasn’t done either at any level since the 2022 college season with Wisconsin. Yet, counterintuitively, he could have been ahead of the curve. Farrar pointed out that the last two Super Bowl champions built substantial confusion for opposing quarterbacks without relying on heavy blitzing. He views that as a major trend in modern NFL defense and sees many of the same principles in Leonhard’s 2022 Wisconsin scheme. For many, Farrar’s assessment of Leonhard’s work as a college defensive coordinator offers a potential early glimpse into what the Bills might implement.
“Players and defensive coaches today must ensure everything is interconnected: the front, the linebackers, the secondary—regardless of how the alignment changes from snap to snap. That’s the crux of post-snap movement, whether it’s line stunts or disguised coverages.” Farrar noted that Leonhard employed, even years ago, a considerable number of contemporary NFL concepts. He predominantly used four-man fronts, complemented by a variety of stunts, and orchestrated hundreds of different looks. This background hints at the possibilities for Buffalo’s defense under Leonhard, even if the exact execution in the NFL remains to be seen.