Rex Ryan fires Bills defensive line coach Dunbar

Buffalo Bills head coach Rex Ryan. (Gary Wiepert/AP)

BUFFALO, N.Y. — Rex Ryan’s Buffalo Bills defence is undergoing yet another shake-up this off-season after he abruptly fired defensive line coach Karl Dunbar on Sunday.

The move came as a significant surprise because Dunbar spent the past four years working for Ryan, and because most teams’ coaching staffs are already set by mid-March.

"This was a difficult decision as Karl both played for me and then coached on my staff," Ryan said, in a statement released by the team. "I have a great deal of respect for him. But I feel we needed to make a change and go in a different direction at this point in time."

Dunbar is a former NFL defensive lineman who played for Arizona in 1994-95, when Ryan was a Cardinals assistant. And Ryan was coaching the New York Jets in 2012, when he hired Dunbar to be his defensive line coach. Ryan was hired by the Bills last off-season, and he brought much of his staff, including Dunbar, with him to Buffalo.

Dunbar's firing is the latest change to the Bills defensive staff. In January, Ryan hired his twin brother Rob to serve as the team's assistant head coach with a specific responsibility for defence. Retired five-time All-Pro safety Ed Reed was also hired by Buffalo to be an assistant defensive backs coach.

The changes come after Buffalo's high-priced defensive line struggled in adapting to Ryan's system last year. After combining for an NFL-leading 111 sacks in 2013-14, the Bills managed just 21 last year, a team low for a 16-game season.

Defensive end Mario Williams went public with his complaints in October, questioning whether Ryan's scheme fit the team's personnel. Williams was released by the Bills earlier this month and has since signed with Buffalo's AFC East rival Miami.

The line returns two starters, Marcell Dareus and Kyle Williams.

A defensive specialist, Ryan took partial responsibility for Buffalo's struggles and vowed the defence will be better.

"Obviously, we never had near the results that I anticipated," Ryan said shortly after the season ended. "I'm much more confident now having to go through this that we will get this thing right, I'll get it right."