Another coach leaves Buffalo Bills as team transitions to three new coordinators

The Bills lost a previously important coach to an NFC foe.

Ryan Nielsen served as the Jacksonville Jaguars' defensive coordinator before joining the Bills as an assistant. | Corey Perrine/Florida Times-Union / USA TODAY NETWORK via Imagn Images

When the Buffalo Bills hired Ryan Nielsen, he was expected to help transform the team’s defensive line.

But after middling results and his former boss was let go by the team, Nielsen departed the organization to take a job with a non-conference opponent. According to NFL Network’s Ian Rapoport, Nielsen is headed to Minnesota to serve as the team’s defensive line coach and defensive run game coordinator.

RELATED: Buffalo Bills make best choice hiring Jim Leonhard as defensive coordinator

Jacksonville Jaguars defensive coordinator Ryan Nielsen coaches during an organized team activity Tuesday, May 28, 2024 at EverBank Stadium’s Miller Electric Center in Jacksonville, Fla. | Corey Perrine/Florida Times-Union / USA TODAY NETWORK

Time in Buffalo

Nielsen’s addition to the coaching staff as a senior defensive assistant this past offseason didn’t quite make the impact the Bills hoped for. The Buffalo run defense was the fifth-worst in the NFL, allowing 136.2 yards per game, while the pass rush didn’t fare much better. Buffalo finished with the 12th-best quarterback pressure rate in the league (35.4%), which is where they ranked a season ago (34.9%).

Before he was with the Bills, Nielsen served as the Jacksonville Jaguars' defensive coordinator. He now moves on to the Vikings, where he will serve under defensive coordinator Brian Flores.

MORE: Joe Brady explains reasons Buffalo Bills hired three new coordinators

More additions for the #Vikings: Gerald Alexander will become the defensive pass game coordinator and DBs coach, while former #Jaguars DC Ryan Nielsen comes on as D-line coach and defensive run game coordinator, per me and @TomPelissero.

Daronte Jones left to be Commanders DC. pic.twitter.com/lctod9azP1

— Ian Rapoport (@RapSheet) January 31, 2026

New era

The Bills announced the hiring of new defensive coordinator Jim Leonhard on Saturday, as the 43-year-old takes over after the firing of former head coach Sean McDermott and subsequent hiring of Joe Brady as head coach. Leonhard has never been an NFL defensive coordinator, but has experience in such a role at the collegiate level.

“Jim’s vision of what he wants from our defense and the personality they play with is the exact style of what I was looking for from a defensive coordinator,” said Brady in a statement posted to Bills PR’s X account. “You could tell how smart and versatile his secondary was when we watched them on tape.”

Leonhard has yet to fill out positional coaching roles, as Brady does on the offensive side of the ball, where he will continue to call plays. The Bills also hired offensive coordinator Pete Carimichael and special teams coordinator Jeff Rodgers, along with offensive line coach Pat Meyer.

Jacksonville Jaguars defensive coordinator Ryan Nielsen talks with defensive end Adam Gotsis (96) during an organized team activity Tuesday, May 28, 2024 at EverBank Stadium’s Miller Electric Center in Jacksonville, Fla. | Corey Perrine/Florida Times-Union / USA TODAY NETWORK

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