At one stage in the second set after serving three double faults to drop a service game, the fifth-seeded Dokic threw down her racket and broke it. She escaped without a code violation.
"I was annoyed because I had a chance to win," she said. "It's more annoying to have a chance to win and losing rather than just getting beaten."
Daniela Hantuchova, a former Wimbledon quarterfinalist, and top-seeded Nadia Petrova of Russia also lost in the second round. After dropping the first seven games to France's Tatiana Golovin, Hantuchova quit halfway through the second set, citing a respiratory ailment.
Petrova was ousted 6-4, 2-6, 6-4 by Japan's Shinobu Asagoe, last year's finalist. Petrova double faulted to give Asagoe the decisive break in the seventh game of the final set.
Also out was Eleni Daniilidou of Greece, who retired from her match with Japan's Akiko Morigami with an Achilles strain.
Defending champion Magdalena Maleeva rallied from a set and two breaks down to beat Germany's Anca Barna and reach the third round. The fourth-seeded Bulgarian, once ranked No. 4 in the world, trailed 6-3, 3-0 before recovering to win 3-6, 6-4, 6-3.
Gerry Weber Open
Defending champion Roger Federer needed barely more than an hour to beat Russia's Mikhail Youzhny 6-2, 6-1 in the second round, improving his grass court record to 14-0 over the past two years.
Federer opened the match with an ace and raced to a 4-0 lead before lapses such as hitting long and putting a easy volley into the net enabled Youzhny to break the Swiss and get back into the match at 4-2.
Federer recovered on his next service game, losing only a point and then aggressively finished the set by handcuffing Youzhny by a ripping groundstroke and forcing the Russian to dump a forehand into the net.
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