SHANGHAI - World No. 2 Novak Djokovic overcame a strong challenge from Argentine Juan Martin del Potro to retain his title at the Shanghai Rolex Masters on Sunday evening, winning 6-1, 3-6, 7-6 (7-3) at the Qizhong Tennis Centre.

The victory extends the Serb's winning streak in China to 20-0, after he also clinched the Beijing Open last week.

After seeing two match points saved by his world No. 5 opponent, Djokovic put up a dominant performance in the deciding tie-break to come out tops.

In the doubles, Ivan Dodig of Croatia and Brazilian Marcelo Melo lifted the trophy after beating Spaniards Fernando Verdasco and David Marrero 7-6 (7-2), 6-7 (6-8) 10-2.