Tennis has seen remarkable records that seem nearly unbeatable. Rafael Nadal’s 14 French Open titles, Martina Navratilova’s nine Wimbledon crowns, Steffi Graf’s Calendar Golden Slam, Roger Federer’s 237 weeks as World No. 1, and the 24 Grand Slam singles titles by Margaret Court and Novak Djokovic, highlight absolute dominance and extraordinary consistency in the sport.