Novak Djokovic of Serbia celebrates his victory over Jo-Wilfried Tsonga of France, in Indian Wells, California, following their quarter-final match at the BNP Paribas Open, on March 15, 2013. Djokovic won 6-3, 6-1.Juan Martin del Potro toppled Andy Murray on Friday to book a semi-final showdown with World No. 1 Novak Djokovic at the Indian Wells Masters. Del Potro, ranked seventh in the world and the seventh seed in this combined ATP and WTA tournament, beat World No. 3 Murray 6-7 (5/7), 6-3, 6-1.