Nicolas Almagro bounced in quarters
The eight-seeded Nishikori will face Janko Tipsarevic of Serbia, who advanced after Nikolay Davydenko of Russia retired with a left hip injury just four games into their match. The third-seeded Tipsarevic was leading 3-1.
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"I don't know what the injury is exactly yet," Davydenko said. "I'm a bit scared as I've never had anything like it before. I will still go to Beijing, maybe wait a few days and see what the pain is like."
The second-seeded Troicki failed to serve out the match at 5-2 in the second set but held on for victory at Putra Stadium. Troicki is looking for his first title of the year after losing the final in Sydney in January.
Copyright 2011 by The Associated Press
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