Biggest tennis upsets over the years
Garbiñe Muguruza defeats Serena Williams - 2016 French Open, Final
Spanish ace Muguruza (C) met with defending champion and world No. 1 Williams (L) of the U.S. at the French Open final on June 4. She defeated Williams in straight sets to clinch her first ever Grand Slam win.
© REX/Shutterstock