Shanghai, Oct 13 (IANS): Defending champion Novak Djokovic overcame a second set slump to defeat sixth seed Juan Martin del Potro of Argentina for his second Shanghai Masters title here Sunday.

One day after defeating World No.1 Rafael Nadal in the semifinals, del Potro continued his surging form, grabbing the second set 6-3 after dropping the opening set 6-1, reports Xinhua.

Both players were able to hit winners in the deciding third set and the match was forced into tiebreak where the Serb was more consistent and sealed the set and match 7-3.

By lifting his seventh trophy of the season, the 26-year-old Djokovic improved his slim chances of overhauling Nadal in the battle for year-ending No.1 in the rankings. With the victory, Djokovic improved his winning streak to 20 matches on Chinese soil.

Djokovic earned $729,725 and 1,000 ATP ranking points while del Potro picked up $357,800 and 600 points. Both players have already qualified for the ATP World Tour Finals to be held at The O2 in London from Nov 4-11.