Question for all to answer!

[OHBBREF]

If you can avoid it and ignore it would probably be better to do so -
If you feel that you have to do something about it, find a game manager, point out the fan and tell him that there is a problem and it needs to be handled.

Last time I had an issue like this the administrator went over and sat near the person said "Hi How are you?" and started watching the game with them.
eventually the guy couldn't resist and made an inappropriate comment the administrator had him removed.

At tomorrows game the loudest fan in the gym will be the home teams AD - he never says anything inappropriate and is all over the gym doing his job - but you always know right where he is by sound and he knows right where his troublesome fans are too!