Rafael Nadal, Roger Federer Get Tennis Expert's Nod Over Novak Djokovic. Here's Why

When you get to the level of Rafael Nadal, Novak Djokovic, and Roger Federer, assessing greatness can be like splitting hairs. However, for those who love the sport, analyzing who is the greatest tennis player ever is almost a sport in itself.

For one tennis expert, it's a close call, but, at least by one measurement, Djokovic may end up at the bottom of the pack. Slightly. Ivan Ljubicic, Roger Federer’s former coach and once the third-ranked tennis player in the world, made the controversial...