Timetable:
Draw lots, or choose the two weakest teams
First round: 7 teams bye, 2 teams first round1;
The second round: 7 bye teams +65438+ 0 teams won in the first round, 4 games.
Semi-final: Four teams won in the second round, with two matches.
Final: The two teams that won the semi-final will participate, 1 game.
If fairness is considered, it is suggested to adopt grouping+elimination system.
Nine teams are divided into three groups, each with three teams.
Each group will play a single round robin first, and the first place in each group+the second place with the best performance ***4 teams will qualify.
Four teams drew lots to enter the semi-finals, and the winner competed for the championship.
This requires 9+3= 12 fields.
If there are only 10 games, you can compare the scores and goal difference of the first three teams and choose the two teams with better results to play the final first, so you only need 10 games.