Dana Vollmer looks for her time after competing in the opening heat of the… (Barbara Walton / EPA )
LONDON — Dana Vollmer broke Olympic and U.S. records in the women's 100-meter butterfly on Saturday morning, setting the stage for a challenge to the world record.
Vollmer blew away the qualifying field, posting a time more than one second faster than all of her competitors. Her time of 56.25 seconds beat the American record she set at last month's Olympic trials (56.47) and beat the Olympic record set by Inge de Bruijn of the Netherlands in 2000 (56.61).
"I'm really happy with that," Vollmer said. "I'm always more nervous than the rest. To start off that fast is kind of a confidence-booster."
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The world record is 56.06 seconds, set by Sarah Sjostrom of Sweden in 2009. Vollmer has talked repeatedly of swimming a time of 55-some seconds. The former UC Berkeley swimmer said Saturday that she "hopefully" would set a world record here.
Sjostrom posted the fourth-fastest qualifying time Saturday morning, trailing Vollmer, Ying Lu of China and Alicia Coutts of Australia.
Claire Donahue, the other U.S. entrant, finished seventh in 58.06 seconds.
The semifinals of the event take place Saturday night, with finals set Sunday night.
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