Despite leading 4-3 in the opening set, Roddick was forced off court with a knee injury.
Speaking after the match the 27-year-old American was unsure of the seriousness of the injury.
“I donÃ¢â‚¬â„¢t really know whatÃ¢â‚¬â„¢s going on in there,” he said. “IÃ¢â‚¬â„¢m not a doctor. I canÃ¢â‚¬â„¢t really self diagnose myself, so I donÃ¢â‚¬â„¢t really know.”
“I just felt I pushed off, and then Michal (Novotny Ã¢â‚¬â€œ ATP Trainer) came on court and did some tests and advised that it probably wasnÃ¢â‚¬â„¢t worth the risk until we know more.”
A successful stint in Shanghai would have seen Roddick qualify for the ATP World Tour Finals in London, but this year’s Wimbledon runner-up is still confident of playing at the O2 Arena.
“I think regardless of what I do from here on out, I still have a pretty good shot of qualifying, so thatÃ¢â‚¬â„¢s nice that I do have a little bit of a cushion.”
“I canÃ¢â‚¬â„¢t really worry about that, because itÃ¢â‚¬â„¢s out of my hands right now. WeÃ¢â‚¬â„¢ll move on, and handle what we can handle from here on out.”
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BIOGRAPHY: Cesc Fabregas