Former world number one Lleyton Hewitt made a convincing return to action by winning two matches on Thursday to storm into the quarter-finals of the Mumbai Open.

Hewitt beat 89th-ranked Serbian Boris Pashanski 7-6 6-2 in the rain-interrupted second round, hours after the Australian had brushed aside Taiwan's Chen Ti 6-3 6-3 in a morning match that had been called off on Wednesday due to rain.

Hewitt had pulled out of Sunday's Davis Cup singles rubber against Serbia's Novak Djokovic with a virus as Australia, winners of 28 Davis Cup titles, were relegated from the elite world group.

Pashanski, who beat Sergio Roitman of Argentina in the morning, proved a gritty customer and stretched the 26-year-old world number 21 into a tiebreak in the first set.

The Serbian broke back in the ninth game before a drizzle interrupted play for nearly half an hour with Hewitt leading 5-4.

Hewitt, the second seed, proved unstoppable in the second set, breaking his opponent in the first and fifth games before serving out for the match.

"I played a good game to get out of 5-all and love-40," Hewitt said.

"Had a good start in the second set, got an early break and ran away with it.

"It's nice to be able to win both the matches in straight sets."

Fourth seeded Finn Jarkko Nieminen, fifth seeded Frenchman Fabrice Santoro and German wildcard Nicolas Kiefer also reached the last eight.

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