Serena Williams on Monday escaped with a fine of just $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, that she lost to Samantha Stosur, to be a "major offence" under the Grand Slam code of conduct.

"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 in a statement.

"This fine is consistent with similar offenses at Grand Slam events," said the USTA added. Williams earned $1.4 million at the US OpenĀ -- runner-up prize money was $900,000 and $500,000 bonus.