13 teams in the tournament.
3 teams play in each game.
6 games are played by each team.
26 games are played in the whole tournament.
Each team plays every other team once.
Each team plays on every colour twice.

Game
ABCDEFGHIJKLMNOPQRSTUVWXYZ
Team1R Y GR Y G
2GR Y R Y G
3 GR Y G R Y
4 GR Y G R Y
5Y GR G R Y
6 Y GR G R Y
7 Y GR G R Y
8 Y GR Y G R
9 Y GR Y G R
10 Y GR Y G R
11 Y GR Y G R
12 Y GR Y G R
13 Y GR Y G R

The above grid shows you conceptually how the 13-team grid works, but it contains back-to-backs. Below is a rearrangement of the same grid, with no back-to-backs.

13 teams in the tournament.
3 teams play in each game.
6 games are played by each team.
26 games are played in the whole tournament.
Each team plays every other team once.
Each team plays on each colour twice.

Game
ABCDEFGHIJKLMNOPQRSTUVWXYZ
Team1R G Y Y R G
2G R G Y Y R
3 G R G Y Y R
4 R G R G Y Y
5Y Y R G R G
6 G Y Y R G R
7 G Y Y R G R
8 R G Y Y R G
9 G R G Y Y R
10 G R G Y Y R
11 Y R G R G Y
12 Y Y R G R G
13 G Y Y R G R

12 team Tournament Grids 14 team
League Grids