NFL Legend Buddy Ryan Dead at 82

Ex-NFL coach Buddy Ryan -- one of the great defensive masterminds of all time -- has died after a long battle with cancer ... his agent confirmed. He was 82.

Buddy was a key part of the '85 Bears coaching staff -- and was carried off the field when Chicago won the Super Bowl. He was also a coach on the '68 Jets -- the team that won Super Bowl III.

His sons followed in dad's footsteps -- Rex Ryan is the head coach of the Buffalo Bills and his twin brother, Rob Ryan, is one of Rex's asst. coaches.

Mike Ditka -- head coach of the '85 Bears -- issued a statement saying, "We lost a good one. There will never be another guy like Buddy, believe me."

FYI, Buddy is an Army veteran and served during the Korean war.