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1915 in Argentine football saw the reunification of the Asociación Argentina de Football and the Federación Argentina de Football. Racing won its third consecutive league championship.
The reunification of the Asociación Argentina de Football and the Federación Argentina de Football brought the creation of a championship of 25 teams. The tournament took a league format with each team playing the others once. San Lorenzo de Almagro debuted at Primera División after promoting the last year, which caused all the "big five" to meet in a championship for the first time.
The top two teams finished even on points, which necessitated a championship playoff, which was won by Racing Club.
Asociación Argentina de Football - Copa Campeonato
Racing Club de Avellaneda and San Isidro finished even on points at the top of the table, necessitating a championship playoff, where Racing won its third consecutive title.
^ The first league meenting between Avellaneda rivals Racing Club and Independiente ended 1-2 to Independiente, but the result was cancelled and the points awarded to Racing Club.
Banfield had two results cancelled and the points awarded to their opponents.