NFL mourns loss of coaching icon Ryan

Buddy Ryan, the pugnacious coach who masterminded two fierce defences that won Super Bowl titles and whose twin sons have been successful NFL coaches, died Tuesday, aged 82.

His death was confirmed by the Buffalo Bills, who are coached by Rex Ryan.

James Solano, Buddy Ryan's agent, said he died in Kentucky but did not give a cause. Ryan lived on a ranch in Shelbyville, illinois.

"Buddy was a legend in our league in so many ways," the Bills said in a statement.

"His defences were innovative and he was a master at putting his talented and tough players in a position to succeed. He was a real game changer, and much of his philosophies and defensive tactics are still utilized effectively by teams today."

Ryan was a linebackers coach for the 1968 New York Jets and coordinated the ground-breaking 46 defence for the '85 Chicago Bears, one of the NFL's greatest defenses.

He was a head coach for the Philadelphia Eagles from 1986-90, and for the Arizona Cardinals in 1994-95, compiling a 55-55-1 overall record.