Rohan Bopanna and his Pakistani partner Aisam-ul-Qureshi finished their Indianapolis Tennis Championships campaign on a sordid note after pulling out of their quarter-final encounter midway due to a back injury to the Indian.

The unseeded Indo-Pakistani were trailing 2-6, 0-1 against the Australian-American pair of Ashley Fisher and Tripp Phillips when Bopanna decided to pull out.

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Bopanna and Qureshi, who finished runners-up in last week's Hall of Fame Tennis Championships in Newport, had beaten the fourth-seeded Russian pair of Igor Kunitsyn and Dmitry Tursunov [Images] 2-6, 7-5, 10-6 in the previous round.

Fisher and Phillips will now take on the American pair of Rajeev Ram and Bobby Reynolds in the semi-finals.

With Bopanna's exit, India's challenge also ended in the tournament. Top seeds Leander Paes [Images] and Mahesh Bhupathi [Images] had earlier been shown the door in the opening round.

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