I'm a sports fan. I'm not just an athlete who plays football.

I'm a football fan, a sports fan, a fan of competition.

I'm a big sports fan. Football. Cricket.

I'm a big sports fan. College football is my favorite.

I'm a huge, huge sports fan, and Marquette basketball is my No. 1 thing.

Whereas fanatic is usually a pejorative word, a Fan is someone who has roots somewhere.