The origin of professional football can be traced back to 1892, with William "Pudge" Heffelfinger's $500 contract to play in a game for the Allegheny Athletic Association against the Pittsburgh Athletic Club. In 1920 the American Professional Football Association was formed. The first game was played in Dayton, Ohio on October 3rd, 1920 with the host Triangles defeating the Columbus Panhandles 14-0. The league changed its name to the National Football League (NFL) two years later, and eventually became the major league of American football. Initially a sport of Midwestern, industrial towns in the United States, professional football eventually became a national phenomenon. Football's increasing popularity is usually traced to the 1958 NFL Championship Game, a contest that has been dubbed the "Greatest Game Ever Played". A rival league to the NFL, the American Football League (AFL), began play in 1960; the pressure it put on the senior league led to a merger between the two leagues and the creation of the Super Bowl, which has become the most watched television event in the United States on an annual basis.