I'm pretty sure this idea has been discussed, how about this method:
3 rounds in a match. Each team member plays in 1 round. So it would go like this:
Blue 1 vs Green 1= Green 1 wins.
Blue 2 vs Green 2= Green 2 wins.
Then the Green team advances to the next round.
As for Blue 3 and Green 3 they can have their own round as a bonus round.
But if the match goes like this:
Blue 1 vs Green 1= Blue 1 win.
Blue 2 vs Green2 = Green 2 win.
Blue 3 vs Green 3= Tie.
Then you can just just have another match. And I doubt that that kind of cycle will occur repeatedly.
And yes, I know Kai-V said that there will probably be only 2 members on a team, but if you can, add on to this idea or just ignore it. (:
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