Pakistan tennis ace Aisam Qureshi and James Cerritani of the United States stormed into the quarter-finals of the Basel Open on Tuesday after a straight sets victory overt world No 1 Roger Federer and his Swiss compatriot Marco Chiudinelli.
The Pakistan-US pair won the round of 32 clash in Federer's hometown 6-4, 6-3 and set up a meeting with top seeds and reigning ATP World Tour champions Daniel Nestor of Canada and Serbia's Nenad Zimonjic, who survived a scare in their first-round match to beat South Americans Lucas Arnold Ker and Fernando Gonzalez 4-6, 6-3, 10-5.
Federer, a winner of eight ATP World Tour doubles titles, was playing doubles for just the second time this season, following a first-round exit with Allegro at the BNP Paribas Open in Indian Wells.
In another match, three-time former champions Bob and Mike Bryan made a strong start to their campaign, beating wild cards Yves Allegro of Switzerland and Croatian Ivan Ljubicic 6-1, 6-4.
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