New York, Sep 10 - India's Yuki Bhambri prevailed over American Jack Sock 6-4, 6-3 to move into the quarterfinals of the boys' singles in the US Open tennis championship here Thursday.

Top seed Yuki took 61 minutes to beat Sock in the third round and set up a clash with American Chase Buchanan, who defeated Marton Fucsovics of Hungary 6-2, 6-3.

Yuki, who in January became the first Indian to win a junior Australian Open, has shown impressive form so far and is yet to drop a set.

The Indian served strong in the first set and did not concede a single break point. He broke the American once to take the lead in 31 minutes.

Yuki's serve came under some pressure in the second set as Sock broke him twice, but the Amercian had more trouble holding his own serve and was broken back four times.