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42 teams (the cup title holder, national domestic league champions, and a variable number of other clubs from the most important national domestic leagues) played knock-out rounds on a home and away basis. The aggregate score of both games decided the winner.
The sixteen remaining teams after the knock-out rounds entered the Regular Season Group Stage, divided into two groups of eight teams, playing a round-robin. The final standing was based on individual wins and defeats. In the case of a tie between two or more teams after the group stage, the following criteria were used to decide the final classification: 1) number of wins in one-to-one games between the teams; 2) basket average between the teams; 3) general basket average within the group.
The top four teams from each group after the Regular Season Group Stage qualified for a Quarterfinal Playoff (X-pairings, best of 3 games).
The four winners of the Quarterfinal Playoff qualified for the Final Stage (Final Four), which was played at a predetermined venue.
Team allocation
The labels in the parentheses show how each team qualified for the place of its starting round:
TH: Title holder
1st, 2nd, 3rd, 4th, 5th, etc.: League position after eventual Playoffs
Partizan was drawn for the competition but was not allowed to compete due to UN embargo on FR Yugoslavia. FIBA decided not to replace Partizan with another team for the Regular Season Group Stage, so the 15 qualified clubs had to be unevenly distributed in this round (a group of 8 teams and another of only 7).
**Crvena zvezda was drawn for the competition but was not allowed to compete due to UN embargo on FR Yugoslavia. PAOK went through with a walkover.