Federer versus Nadal always offered contrast: Offense versus defense, righty versus lefty, pace versus spin.

WSJ: Australian Open: The New Normal: Andy Murray vs. Novak Djokovic

If the final is Federer versus Nadal, a Swiss or Spanish umpire won't get the call.

FORBES: Magazine Article

To witness the back-and-forth of their flirtation is like watching Nadal versus Federer on clay.

NEWYORKER: Hot and Bothered

It's a rivalry defined by strength (Nadal's left-handed forehand) versus relative weakness (Federer's one-handed backhand), and Federer knows there's little point in hanging back and rallying with Nadal for hours.

WSJ: Djokovic, Nadal Could Wear Each Other Out Before Paris