Top seeds Mahesh Bhupathi [Images] and his Serb partner Nenad Zimonjic beat Spaniards Nicolas Almagro and Fernando Verdasco in straight sets to advance to the quarterfinals of ATP Pilot Pen Classic tournament in New Haven, USA.

The Indo-Serb pair came through 7-5, 6-3 against their unseeded rivals in the first round of the USD 675,250 event on Monday.

Bhupathi and Zimonjic will now be up against another unseeded Spanish pair of David Ferrer and Albert Montanes in the last-eight stage.

Ferrer and Montanes beat the Argentine duo of Agustin Calleri and Juan Monaco 7-6(3), 7-6 in their first-round match.