Rafael Nadal faces a fight to hold on to his world number one ranking after Novak Djokovic extended his victory streak to 34 matches with a 7-5, 6-4 win over the Spaniard at the Madrid Masters on Sunday.

Nadal had to swallow his first loss on clay in nearly two years, a run of 37 straight victories stretching back to the French Open fourth round in 2009 when he lost to Robin Soderling.