India's Somdev Devvarman and his Australian partner Nathan Healey stretched their impressive run in the US $ 50,000 Calabasas Challenger event, advancing to the semi-finals after beating Prakash Amritraj and Alex Kuznetsov in California.

Somdev and Healey, who entered the event as qualifiers, beat the Indo-American pair 6-4, 4-6, 10-7 in the quarter-finals of the hard-court event.

The duo had toppled third seeds Todd Widom and Van Der Merwe 6-7, 6-3, 10-6 in their first round match. They next play another giant-killing American pair in Brian Battistone and Dann Battistone, who had upset compatriots and top seeds Rajeev Ram and John Isner in their first round match.

Somdev's singles campaign was cut short in the first round itself and now Amritraj is the lone Indian left in fray in the singles draw.

He faces American top seed Vincent Spadea in the quarter-finals.

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