Mario Ancic (flu) and Robin Soderling (flu, shoulder) have joined Tim Henman (knee), Sebastien Grosjean, Richard Gasquet (exhaustion) and Marcos Baghdatis (wrist) in dropping out of the tournament, which begins Monday.
"These players bring a great deal of energy to the court," said Richard Krajicek, the tournament director, who was scheduled to play Gasquet in the first round.
The Czech Republic's Radek Stepanek is the defending champion. His 2006 title is his only championship on the WTA tour.
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