In most sports there is a main city where people gather to play, so the city is the primary regional identifier. Next, there can be a club(s) which will help narrow down the list of people and associated events.
This app stores the city, club and your name in a cookie that automatically fills in when you open the app to save time and then looks up the information to see if anyone has initiated a playing event.
Clicking the red “X” will remove that entry, if it is an Initiator, the next person will be come the Initiator.
Demo below using City = New York City and Club = usopen