Serena Williams has avoided a ban from tennis after tournament officials decided her US Open final outburst did not constitute a major offence.

The 29-year-old was given a code violation for verbal abuse during the women's singles final, which she lost to Sam Stosur, when she harangued umpire Eva Asderaki and then continued to insult the official at the next change of ends, calling her "out of control", a "hater" and "unattractive inside".

Williams was playing under a suspended ban from the 2009 tournament, when her infamous verbal attack on a lineswoman cost her a point penalty in the semi-final against Kim Clijsters, which could have seen her barred from the 2012 US Open for another major offence.

But a statement released by the United States Tennis Association read: "US Open tournament referee Brian Earley has fined Serena Williams 2,000 US dollars following the code violation issued for verbal abuse during the women's singles final.

"This fine is consistent with similar offences at Grand Slam events. As with all fines at the US Open, the monies levied are provided to the Grand Slam Development Fund which develops tennis programmes around the world.

"After independently reviewing the incident which served as the basis for the code violation, and taking into account the level of fine imposed by the US Open referee, the grand slam committee director has determined that Ms Williams' conduct, while verbally abusive, does not rise to the level of a major offence under the grand slam code of conduct."

Williams was battling to hang onto her serve at the start of the second and thought she had saved a second break point when she let out a huge cry of "come on".

But the ball had not yet reached Stosur and, under grand slam rules, a deliberate hindrance, such as an intentional shout during a point, sees the perpetrator lose the point.

The decision was greeted with an angry response by the American, who went on to lose 6-2 6-3.

Williams, who did not shake Asderaki's hand, refused to apologise after the match and was unwilling to discuss the incident, saying only: "I don't even remember what I said.

"It was just so intense out there. It's the final for me. I guess I'll see it on YouTube. I don't know. I was just in the zone. I think everyone when they play kind of 'zones out'."