Roger Federer and Novak Djokovic are two of the greatest tennis players in history. But who is the best? A former World No. 7 player and Olympic gold medalist has the answer.

Novak Djokovic dropped a set but regrouped to reach the Australian Open third round on Wednesday and in doing so surpass fellow great Roger Federer for the most Grand Slam singles matches played. The 37-year-old faced stiff resistance from fearless Portuguese qualifier Jaime Faria before winning 6-1,