Mahesh Bhupathi [Images] remained well on course to his second successive Pilot Pen doubles title after the Indian ace and his Bahamian partner Mark Knowles eased into the semi-final with a straight sets victory in New Haven.

Bhupathi, who clinched the doubles title with Ninad Zimonjic last year, and Knowles beat Americans Eric Butorac and Scott Lipsky 6-4, 6-4 to enter the semis of the hard court event.

The second-seeded Indo-Bahamian pair will now be up against Italians Simone Bolelli and Andreas Seppi, who beat Spaniards Guillermo Garcia-Lopez and Fernando Verdasco 7-6 (5), 6-7 (2), 13-11 in a cliffhanger.

Although a straight-set victory, it was hardly a cakewalk for Bhupathi and Knowles who were tested by their unseeded rivals.

The Americans could have caused more trouble to Bhupathi and Knowles had they not let slip too many opportunities, especially in the opening set.

The second seeds saved as many as five break points, while Butorac and Lipsky lost their serve twice in the first set that could have been an engaging affair had the locals capitalised on Bhupathi and Knowles' mistakes.

Having managed to stave off the initial resistance, it was relatively easier for Bhupathi and Knowles in the second set and they controlled the proceedings, holding serve and breaking their rivals once, before wrapping up the issue in their favour.

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