Indian Davis Cupper Prakash Amritraj prevailed over Ivan Miranda of Peru in straight sets to set up a quarter-final with top seed Vincent Spadea in the US $50,000 Calabasas Challenger event in California.
Amritraj won the second round hard-court event match 6-4, 6-3.
Ranked 227 in the ATP list, Amritraj has a daunting task against Spadea, currently ranked 89 but once in the top-20.
The Indian also tasted success in the doubles event as he teamed with American Alex Kuznetsov to book a quarter-final berth.
The Indo-American pair defeated Colin Ebelthite of Australia and Peter Polansky of Canada 6-2, 4-6, 11-9 in a second round match.
They next face qualifiers Somdev Devvarman and Nathar Healey of Australia, who stunned the third seeded pair of Izak Van Der Merwe and Todd Widom in the second round.
The Indo-Australian pair made a remarkable comeback to beat the formidable Russian-American pair 6-7(1), 6-3, 10-6.
Somdev bowed out of the singles after losing his first round match to Alex Bogomolov Jr.