Milestone: the age Serena Williams was when she won her first Grand Slam title.
Serena Williams beat world No. 1 Martina Hingis in the US Open final on September 11, 1999, for her first Grand Slam singles title.
Sources: Wikipedia · Tennis Majors. Ages are calculated, not estimated.
Enter your birthday to see the last milestones you passed. Free – we keep your birthday only if you sign up, and your next milestone comes as a surprise.