The U.S. Open has fined Serena Williams $10,000 for her tirade directed at a line judge at the end of a semifinal loss to Kim Clijsters.

It’s the maximum on-site fine a Grand Slam tennis tournament can issue for unsportsmanlike conduct.

The U.S. Open said the Grand Slam Committee Administrator has opened an investigation to determine whether Williams’ behaviour should be considered a “major offence,” which can lead to additional penalties.

Williams also is being docked $500 for racket abuse in what became a 6-4, 7-5 loss on Saturday night.

Williams earned $350,000 in prize money for reaching the singles semifinals. She also is scheduled to play in the women’s doubles final on Monday with her sister Venus.


Clijsters stuns Serena in US Open semi-finalsSeptember 13, 2009

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