Bill Belichick released a statement on Buddy Ryan's passing Tuesday afternoon.
"Today is a sad day in football due to the passing of Buddy Ryan," Belichick said. "It was always very challenging to compete against Coach Ryan, who was father to a great football family that carries on his coaching and defensive tradition. My condolences are with the Ryan Family."
Belichick is certainly very familiar with Ryan's legacy and the tradition Ryan passed down to his sons Rex and Rob. The Patriots coach has competed against all three.
Rex Ryan has squared off with Belichick during his time as head coach for the Jets (2009-14) and Bills (2015-present), and their matchups go back to Rex's days with the Ravens (1999-2008) when he was a defensive line coach and then defensive coordinator.
Rob Ryan, like his brother, got his first NFL break when his father was the head coach of the Cardinals in the mid-1990s. His second break, though, came from Belichick. He joined the Patriots staff during Belichick's first year as head coach in 2000 and coached linebackers for four seasons in New England. He has since competed against Belichick as a defensive coordinator for the Raiders, Browns, Cowboys and Saints. Rob joined Rex in Buffalo this year to serve as an assistant on the staff there.
For Belichick's thoughts on the impact of Buddy Ryan's famous "46" defense, we dug up some of his comments from a 2012 press conference that you can find here. He called the combination of Ryan's scheme and the talented players Ryan had at his disposal as defensive coordinator of the 1985 Super Bowl champion Bears "pretty unblockable."