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.

The Australian Open has witnessed tennis legends leave their mark, and Novak Djokovic reigns supreme with a record-breaking 10 finals appearances, all converted into victories. Roger Federer follows with seven finals,

MELBOURNE, Australia (AP) — Novak Djokovic added yet another record to his lengthy list, breaking a tie with Roger Federer for the most Grand Slam matches played in tennis history by reaching 430 on Wednesday at the Australian Open in what was a tougher-than-expected second-round victory.