Indian Davis Cupper Prakash Amritraj continued his sizzling form to storm into the quarter-finals of the US $ 75000 ATP Challenger tournament in Aptos after posting a convincing straight sets win.

Prakash, who had knocked out top seed Amer Delic in the first round, beat American wild card Phillip Simmonds 6-4, 6-2 in the second round.

However, Prakash and his American partner Lestor Cook bowed out of the doubles event after losing their  quarter-final tie.

The Indo-American pair lost 7-6 (3), 4-6, 4-10 to Israeli pair of Noam Okun and Amir Weintraub in a gruelling contest.

Meanwhile, the Indian pair of national champion Ashutosh Singh and Davis Cupper Harsh Mankad advanced to the semi-finals of the ATP Challenger tournament in Manchester after demolishing their opponents in straight sets.

The fourth seeded Indian pair outplayed Czech pair of Pavel Snobal and Jan Vacek 6-1, 6-1 in the quarter-finals.

However, Indian challenge had ended in the singles event after the first round defeats of Mankad and Purav Raja.

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