Dhaka, Aug. 28 -- Novak Djokovic overcame another sluggish start to move into the third round of the US Open, defeating American qualifier Zachary Svajda 6-7 (5), 6-3, 6-3, 6-1 at Arthur Ashe Stadium on Wednesday.

The 24-time Grand Slam winner, who dropped the opening set, extended his flawless record in New York's first two rounds to 36-0. He has lifted the trophy here four times.

Svajda, 22, stunned the crowd by taking the first set but later struggled with cramps as Djokovic found his rhythm. "He was missing a little bit . he was getting a little frustrated," the American said afterward.

Djokovic, 38, admitted he is still searching for form following a groin injury that hampered him at Wimbledon. "It's not about motivation . I just ...