New York, Sep 6: Serbian tennis star Novak Djokovic defeated Ukrainian Alexandr Dolgopolov 7-6 (16-14), 6-4, 6-2, at New York's Louis Armstrong Stadium on Monday to reach the quarterfinals of the US Open.

Djokovic has now won 61 of the 63 matches he has played in 2011.

The World No. 1 said that Dolgopolov showed no fear and used an array of shots around the court to wrong-foot him.

"It was strong wind, tricky conditions, he's the kind of player who knows how to play in these conditions," the Age quoted Djokovic, as saying.

"I was confused on the court the first set, but it was really exciting -- really exciting," he added.

Djokovic will now face Davis Cup teammate Janko Tipsarevic in the last-eight clash. (ANI)