Serena Williams only hauled in $62,000 in winnings from June 2017 to June 2018 as she was away from the game while pregnant, then gave birth to her daughter Alexis Olympia Ohanian Jr.
However, she has many blue-chip sponsors including Nike, Audemars Piguet, Gatorade, and Beats by Dre, and made an astonishing $18 million in endorsements. Not bad work if you can get it.