 The fields are expanded as one hundred twenty-eight singles players and 64 doubles teams are featured in the main draws.Prior to 1990 professional men's tour tennis consisted of two competing tennis circuits, the Grand Prix tennis tour and World Championship Tennis.This was particularly true during the 1970s, when tour tennis was started in its current format - previous to this, during the 1930s through to the 1960s, touring professional players tended to play exhibition matches instead of tournaments, as they were given appearance money instead of prize money.