Instead of using Recreation Management's automatic matchup generator, you may decide to create matchups manually.
When you create a matchup, it will become an Unscheduled Matchup. After you create the unscheduled matchup, you can manually schedule the matchup or use the system auto-scheduler.
Instructions
Navigate to Activities > League Management
Expand a League
Select Access League Management (basketball icon) next to the desired league session
Select the Game Schedule tab
Hover over the Step 1: Matchups button and select Create Single Matchup
Select a Home Team and a Visitor Team
Select Create
Drag and drop the new matchup into the schedule, or use the auto-scheduling function