Top seeds Leander Paes [Images] and Lukas Dlouhy began their campaign for back-to-back titles with a straight-set win against Spanish pair of Guillermo Garcia-Lopez and Ivan Navarro in the first round of the US $ 869,000 Japan [Images] Open in Tokyo on Thursday.

The Indo-Czech pair, who won the Thailand Open last week, beat the unseeded Spanish duo 6-4, 7-5 in one hour and 13 minutes to advance to the quarter-finals of the hard court event.

However, it was curtains for Rohan Bopanna and his American partner Eric Butorac, who put up a valiant fight against the second seeded pair of  Simon Aspelin and Julian Knowle but eventually lost 7-6 (4), 6-7 (4), 4-10 to bow out of the event.

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