The eighth seeds beat the fourth seeded Indo-Czech combine 6-3, 6-7(3), 10-8.
Bopanna will now be looking to reach his second consecutive Cincinnati final when the Indo-French pair take on second seeded Spanish duo of Marcel Granollers and Marc Lopez.
Granollers and Lopez beat Mariusz Fyrstenberg and Marcin Matkowski of Poland 6-4, 6-2 in the other quarter-final.
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