Serena Williams on Monday escaped with a fine of $2,000 for her US Open final rant, when she launched an angry tirade against the chair umpire in Sunday's title match.

The American, who was under a Grand Slam probation for another outburst at the tournament in 2009, could have faced a ban if officials had deemed Sunday's tirade in the final, which she lost to Samantha Stosur, to be a "major offence".

Williams was handed a code violation by Greek umpire Eva Asderaki after the first game of the second set against Stosur, when she had been docked a point for "intentional hindrance" when she screamed "C'mon" before Stosur had a chance to put her racquet on the ball in a rally.

The incident came on a break point, giving Stosur a break of serve.

Williams berated Asderaki after the game and continued to complain bitterly during the subsequent changeover.

"US Open tournament referee Brian Earley has fined Serena Williams $2,000 following the code violation issued for verbal abuse during the women's singles final," the US Tennis Association said on Monday.

"This fine is consistent with similar offenses at Grand Slam events," said the USTA, adding that the money would go to the Grand Slam Development fund.

Williams earned $1.4 million at the US Open.

Her runner-up prize money was $900,000, and she made a $500,000 bonus for finishing first in the standings of the US Open Series of hardcourt tune-up events in the weeks before the final Grand Slam of the season.

The USTA also said Grand Slam committee director Bill Babcock determined "Williams' conduct, while verbaly abusive, does not rise to the level of a major offence under the Grand Slam Code of Conduct."

The scene recalled her profanity laced tirade toward a line judge in a 2009 semifinal against Kim Clijsters.

AFP