these are the most famous athletes in the world. most of these are footballers because football is a global sport.
http://www.ranker.com/list/most-famous-athletes-in-the-world/killpewdiepie10,
Andrés Iniesta
Cristiano Ronaldo
David Beckham
Kaká
Kobe Bryant
Lionel Messi
Michael Jordan
Roger Federer
Ronaldinho
Neymar