Hello! I need to implement an algorithm to create round-robin tournament schedules, but with the constraint that up to 2 teams – that may play in different leagues – might share the same field on the same time slot of the week, so they must be never be scheduled to play at their home field in the same round of their league schedule. Simple example:

leagueA = [
TeamA(plays at FieldA on Sunday),
TeamB(plays at FieldB on Sunday),
TeamC(plays at FieldA on Saturday),
TeamD(plays at FieldD on Saturday)
]
leagueB = [
TeamE(plays at FieldA on Sunday),
TeamF(plays at FieldF on Sunday),
TeamG(plays at FieldG on Saturday),
TeamH(plays at FieldF on Saturday)
]

I was thinking of generating the schedule for leagueA with the circle algorithm alternating home and away at each round as described in the linked article, and then to approach the scheduling for leagueB by prefilling the slots for the teams that share the field with teams in the other league somehow, but I'm not sure whether it's the right approach and how to actually implement it in a way that is guaranteed to produce schedules do not produce conflicts. Any help would be highly appreciated!