 A player could be substituted for any reason; however, once substituted, a player could not return to the field of play under any circumstances.Teams played each other in a home-and-away season of 19 rounds.There was an extra round (round 8), in addition to 1951's 18 rounds, promoted as a "National Day Round", and held on the Saturday (14 June) of the Queen's Birthday weekend while the Victorian State side played against the West Australian State side at Melbourne Cricket Ground (also on 14 June).