1965 Browns
The Browns hardly fell off the face of the earth the year after beating the highly-favored Colts. With Jim Brown rushing for 1,544 yards and 17 touchdowns in what wound up being his final season, they again reached the NFL Championship Game in the last year before the Super Bowl came into being.
Their opponent this time was the Green Bay Packers, and the task was made even more difficult by a muddy Lambeau Field playing surface. Paul Hornung and Jim Taylor were not as adversely affected by the slop as Brown was, and the Packers ran to daylight through the freezing rain to a 23-12 victory. The championship was the third of five won by the Packers during the 1960’s under Vince Lombardi, the coach for whom the Super Bowl trophy is named.