"The fan is going on the court."

Translation: Ο φίλαθλος πηγαίνει στο γήπεδο.

[jeanprendiville]

Does " Ο θαυμαστής" refer to fans of singers etc.?

[jaye16]

Yes, that would be right. In general wherever "admirer" would be used.

[jeanprendiville]

Ευχαριστώ, είμαι θαυμαστής σας :-)