2009 foot fault
During a semifinal match against Kim Clijsters in 2009, Williams was given a point penalty at match point after an altercation with a lineswoman.
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She had, earlier in the game, been given a code violation for breaking her racquet. Williams later flared-up at the lineswoman who had called a foot fault against her. After review by the umpire, Williams was given a second code violation, leading to her loss against Kim Clijsters.
She was also given a hefty fine (($82,500) after the game and was put on probation.