The format has changed from year to year. For the most part it has been used a precursor to the league season, with 6 groups of 4 teams (geographically based), with the winners and two best runners up going on to the last eight (which started the knockout phase). The knockout stage would be played midweek through the season. In the late 1990s the cup went into a straight knockout format and recently has reverted to again starting with a group phase, this time with 8 groups of 3 with only the winners progressing. In 2006, the competition was once again contested on a straight knock-out basis, with a convoluted regionalised seeding system determining pairings and byes in the early rounds.