TOKYO -- There are always winners and losers in sports, but tennis is particularly unforgiving in that the performance gap is directly reflected in players' incomes.
Naomi Osaka, one of the world's top women's tennis players, placed 29th on Forbes' list last month of the world's highest-paid athletes with income of $37.4 million -- a record for a female athlete. Roger Federer became the first tennis player to lead the list, beating out soccer superstars Cristiano Ronaldo and Lionel Messi with $106.3 million.
