Whether it be McEnroe and Borg, Sampras and Agassi, or Federer and Nadal, the great rivalries have kept tennis fans at the edge of their seats ever since the open era began. So it should be with sadness that possibly the greatest rivalry of all time is coming to an end. In any other period it would be, but in the golden vain of tennis that graces audiences in 2013 it is with great anticipation that the reign of Rafa and Roger is over, to be replaced by the world number 1 and 2 Novak Djokovic and Andy Murray. Having loved tennis since I was 5, my inspiration and idol has always been Roger Federer. It was with hostility that I saw the arrival of Rafael Nadal, the feisty Spaniard who would go on to challenge Roger like no one else, almost questioning Federers title as the greatest player (in my humble opinion) ever to live, almost. This rivalry, spanning 30 matches, has arguably provided the highest standard of tennis ever seen. But the rule of the two Rs is over, and whilst Federer will always be my first love in the game, I for one am happy. Remarkably, another great rivalry is already looming, set to dominate for the foreseeable future. Heres why...