World Number One Novak Djokovic of Serbia has made a shock exit from the Indiana Wells Open Tennis tournament.In the Men's Singles semi-finals at California this morning, Djokovic was stunned by seventh seed Juan Martin Del Potro of Argentina, 6-4, 4-6, 4-6.On the other hand, Spain's Rafael Nadal, who has made a remarkable comeback after a knee injury, stormed into the finals, after beating Tomas Berdych of the Czech Republic, 6-4, 7-5. World Number Five, Nadal, who had defeated World Number 2 Roger Federer of Switzerland in the semi-finals, is now just one victory away from notching his 600th triumph and also the third consecutive trophy on the ATP World Tour.