To see Roger Federer and Rafael Nadal facing each other on the tennis court is to watch one of the greatest rivalries in the history of the sport. Their on court relationship is so legendary that there's even a Wikipedia page dedicated to it. For those not in the know, Roger Federer had held on to the No.1 seed position for a record 237 consecutive weeks until a young Spanish upstart named Rafael Nadal swooped in to take the lead. Since then, they've been taking turns to leapfrog over one another to be No. 1, depending who's cursed with injuries or simply having a slightly off season.

It would be natural to assume that Federer and Nadal have a similar fiery relationship off the court - it must take a hell of a lot of vitriol to whack those balls at each other with such force, wouldn't it? Even if they act chummy for the press, one can't help but wonder if it's all just an act.

But then this video on YouTube arises, which quashes that sentiment in its tracks.

The behind the scenes video is part of a promotional spot for The Match of Africa, a charity match between Federer and Nadal that will be played in Zurich on 21st December in aid of Federer's charity foundation. In the video both players are seated casually in front of camera and trying to get their lines out, but one is hit by a spot of giggles which volleys to the other causing both to burst into uncontrollable fits of laughter much to the exasperation of the director.

It's a golden moment that reveals a rare and warm relationship between two sporting legends.