 Between 1950 and 1961, the NFL also attempted exhibition matches against the Canadian Football League (mixing NFL and CFL rules), but these, too, were abandoned after the 1961 preseason, as the NFL won all six matchups.The CFL finally won a game against American opposition in August 1961, but this was against an American Football League team; as a result of the embarrassment, the AFL opted not to play the CFL again beyond that one game.From 1967 to 1969, during the transition period leading up to the formal AFL–NFL merger, the NFL and American Football League played each other in a series of exhibition matches; notably, the 1969 match between the Buffalo Bills and Washington Redskins was the only time Vince Lombardi ever lost to an AFL team.