Joe Brady Trusting Jim Leonhard to Build Bills' Defense 'We Can All Be Proud of'

The Buffalo Bills fired head coach Sean McDermott in the wake of another postseason defensive failure.

For the seventh year in a row, McDermott's defense failed to do enough late during an elimination game. The Bills, who played soft coverage while allowing a crucial 3rd-and-11 conversion late in the fourth quarter, surrendered 33 points to an offensively-challenged Denver Broncos team with a second-year quarterback.

Following another instance of crashing into the "playoff wall," the Bills installed Joe Brady as the head coach, who then hired Jim Leonhard to run the defensive operations.

Leonhard, who was the defensive pass game coordinator for those aforementioned Broncos, boasts a strong resume for a first-time NFL defensive coordinator.

MORE: Bills' Assistant Coaching Hires Signal Major Defensive Changes under Jim Leonhard

The 43-year-old Leonhard's past includes 10 years as a NFL safety and six seasons as Wisconsin defense coordinator. He also served a stint as his alma mater's interim head coach in 2022.

In 2025, the Broncos held opponents to the fewest yards per pass play (5.37) in the NFL. As a whole, the defense ranked first in yards per play allowed (4.46).

Jim Leonhard coaching — Nov 26, 2022; Madison, Wisconsin, USA; Wisconsin head coach Jim Leonhard talks with Wisconsin wide receiver Keontez Lewis (3) | Mark Hoffman-Imagn Images

Leonhard given defensive autonomy

With Joe Brady planning to call offensive plays, the first-time head coach is placing a high level of responsibility on Leonhard to get the defense right. The former Bills' safety mentioned that the opportunity to build the unit was one of the reasons he decided to take the job.

"The other exciting piece about talking with Joe Brady is kind of the autonomy he's giving me to get the right people in the building as far as coaches. And let's create a defense that we can all be proud of. Let's create a defense that the NFL does not want to play against," said Leonhard.

The defensive coach's adaptability is a trait that caught Brady's attention.

"You can tell he has a clearer vision for what he's looking for, but he adapts," said Brady. "He has versatility. He's willing to say, okay, hey, this is ideal, but if we don't have this, well, then we're going to have to be able to do this, this and this."

As for what to expect from Leonhard's unit in 2026, the former undrafted free agent promises aggression.

"We're going to be an attacking defense up front, in the back end. We're going to attack the football," said Leonhard. "We're going to be aggressive. We're going to fly around. We're going to communicate.

Jim Leonhard INT — Sep 22, 2013; East Rutherford, NJ, USA; Buffalo Bills defensive back Jim Leonhard (35) intercepts a pass for New York Jets wide receiver Santonio Holmes (10) during the first half at MetLife Stadium. | Robert Deutsch-Imagn Images

Bills' offensive coordinator 'fired up'

Brady tabbed NFL coaching veteran Pete Carmichael as the Bills' offensive coordinator, and he's someone who worked on the same staff as Leonhard the past two seasons with the Broncos. Carmichael, who was the New Orleans Saints' offensive coordinator in Super Bowl XLIV, was excited to hear that Leonhard joined the staff in Buffalo.

MORE: Bills' Organized Team Activities Start Two Weeks Early This Spring

"Jim is a great communicator. You can see the relationship that he has with his players and the amount of respect they have. When he's talking, there's a real presence about him, calmness that I think the players just kind of gravitate towards him," said Carmichael. "When Joe said he was trying to hire him initially, I was like 'yea, we gotta get this guy.' I was fired up."

Oct 12, 2025; Tottenham, United Kingdom; Denver Broncos senior offensive assistant coach Pete Carmichael watches during an NFL International Series game against the New York Jets at Tottenham Hotspur Stadium. | Kirby Lee-Imagn Images