Flavia Pennetta advances
Mattek-Sands replaced Britain's Laura Robson, who pulled out because of a right wrist injury. Known for colorful outfits, Mattek-Sands wore black socks and wrist bands with a streak of green in her blonde hair.
The 32nd-ranked Robson was coming off a strong performance at Wimbledon where she reached the fourth round -- the first British woman to do so since 1998.
Copyright 2013 by The Associated Press
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