Novak Djokovic is opening up about his relationship with fellow tennis stars Roger Federer and Rafael Nadal, admitting that it's often strained.

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 -- And then there was one: The Big Three is down to just Novak Djokovic, who stands alone from a golden generation of men’s tennis now that Rafael Nadal has joined Roger Federer in retirement.