(ABC News) -- Serena Williams said she’s “heartbroken” to leave Wimbledon and blamed a “bug” for the strange symptoms that caused her to forfeit her doubles match Tuesday.
The 32-year-old tennis star, who won the U.S. Open last fall, was forced to forfeit the match after struggling to bounce, catch and serve the ball.
Wimbledon tweeted that Williams was “suffering from a viral illness” as she left the court hand-in-hand with her sister, Venus.
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“I thought I could rally this morning, because I really wanted to compete, but this bug just got the best of me,” Williams said in a statement.
Experts called the behavior “very unusual.”
“I’ve seen her play before,” said Dr. Dr. George Kikano, who practices family medicine at University Hospitals Case Medical Center in Cleveland, Ohio, and has not treated Williams. “She is a master on the court. She does not miss a ball. She does not miss a beat. She does not miss a serve. This is very unusual for her.”
Kikano said Williams appeared to be confused, which could be a sign of dehydration caused by a virus, bacteria or the environment. She could also have been experiencing side effects from some kind of medication or she might have just been exhausted.
Dr. William Schaffner, chairman of preventive medicine at Vanderbilt University Medical Center in Nashville, Tennessee, said Williams didn’t appear to be suffering from a neurological virus because she was still able to walk on her own. He echoed Kikano’s theory that dehydration could have been to blame.
“That could be a consequence of any number of viral illnesses,” he said. “It’s still too vague to comment on unless they give us more details.”
Williams had another health scare in 2011 when she suffered a blood clot in her lungs following a foot injury and surgery.
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