NFL's 20 greatest coaches

We begin with apologies to Chuck Knox. All he did is win more games than all but eight other coaches in NFL history. Sorry to Tom Flores, too, whose two Super Bowl rings weren't enough for inclusion.

Naming the top 10 coaches of a generation is tough enough. Deciding the top 20 from half a century of football is almost laughably impossible.

The criteria: The most successful coaches from the modern era, meaning men who coached the majority of their career post-1950. That omits legends like Curly Lambeau and George Halas, and others who were edged out because of the extreme competitiveness.

By Danny O'Neil, The Seattle Times