I have a problem with group matchin. In my desgin, participants have either role A or B. There are twgames. In game 1, each group indludes 1 A and 1 B. In game 2, the strudcture is the same, but I want to sure that each player has different coparticipant. (If I keep the rola As and randomise rols Bs, there is a pborability that the same A and B are matched in the second game). 

To clear my question, let say there are 10 parcitipants. game 1 includes 5 groups= [A1, B1], [A2, B2] ...[A5, B5]. I want to be sure in the secone game A1 has a coparticipant except B1, A2 has a coparticipant except B2, ....., A5 has a coparticipant except B5. 

I would be so thankful if anybody can help me out.