The Women's Tennis Association (WTA) has backed Serena Williams after she was hit with a $17,000 (£13,100) fine over her conduct during the US Open final.

Williams received three code violations during her defeat to Japanese star Naomi Osaka on Saturday - one for coaching from the stands ($4,000/£3,100), one for throwing her racket down in anger ($3,000/£2,300), and another for calling umpire Carlos Ramos a "liar" and a "thief" ($10,000/£7,700).

The 23-time grand slam singles champion - who earned $1.86m (£1.43m) for reaching the final at Flushing Meadows - launched an explosive tirade towards the Portuguese, claiming she was being treated differently to how a man would be in such circumstances.

Image: The largest portion of Serena Williams's fine was the result of her row with Mr Ramos

Image: She was also fined for racket abuse

She has received plenty of support from across the tennis world, including from Billie Jean King, and has now been backed up by WTA chief executive Steve Simon.

In a statement, Mr Simon hailed Osaka as a "deserving new champion" but said Williams was right to suggest that she had been on the receiving end of sexism by Mr Ramos, who has previously attracted the umbrage of other tennis stars, including Andy Murray and Rafael Nadal.


"The WTA believes there should be no difference in the standards of tolerance provided to the emotions expressed by men versus women and is committed to working with the sport to ensure that all players are treated the same," he said.

"We do not believe that this was done last night."

The US Tennis Association, which issued the fines, has not responded to the comments by Mr Simon, which were made after Novak Djokovic won the men's final against Martin del Potro.

Djokovic said he had sympathy for Williams and Osaka, who became the first Japanese player to win a grand slam, but did not agree that Mr Ramos had been sexist.

"I have my personal opinion that maybe the chair umpire should not have pushed Serena to the limit, especially in a grand slam final - he did change the course of the match," the Serb said.

"We all go through our emotions, especially when you're fighting for a grand slam trophy.

"But I don't see things as Mr Simon does. I really don't. I think men and women are treated in this way or the other way depending on the situation. It's hard to generalise things. I don't see it's necessary really to debate that."

Image: Williams asked for the judge's supervisor to intervene after the points were docked

Image: Serena Williams was tearful during the presentation

The arguments between Williams and Mr Ramos cast a shadow over the final, which ended with Osaka being booed by some of the crowd.

Williams had accused Mr Ramos of being a liar when he penalised her for cheating, saying she would rather lose than cheat to win and telling him he would "never, ever be on another court of mine".

In a news conference after the match, Williams, 36, said she was "fighting for women's rights" and for equality on the tennis court.

She said: "I've seen other men call other umpires several things. I'm here fighting for women's rights and for women's equality and for all kinds of stuff.

"For me to say 'thief' and for him to take a game, it made me feel like it was a sexist remark. He's never taken a game from a man because they said 'thief'. It blows my mind."

Although she drew criticism, there were many who supported Williams, including Andy Roddick and Sue Barker.

Image: Naomi Osaka of Japan holds the US Open trophy after beating Serena Williams

Image: Williams said she felt there was sexism at play in the dispute

Former French Open winner Barker said: "Serena in some ways has a point in the fact that I've sat court-side watching the men ranting at umpires and (they) haven't been given a violation.

"Serena is saying the male players can say what they like to an umpire.

"Also, earlier in the tournament we saw Alize Cornet being given a code violation for changing her shirt on court.

"Then, in the same tournament, Mohamed Lahyani gets off the umpires' chair to talk to Nick Kyrgios and persuade him not to give up on a match.

"So I think they have to look at the rules of what is allowed and what isn't, because I just think he was following the rules absolutely by the book, but sometimes the book has to be re-written - you can't have one rule for some players, and some umpires don't adhere to it and allow players to get away with things."

Image: Naomi Osaka and Serena Williams hug at the end of the match

Roddick tweeted it was the "worst refereeing" he had ever seen, and Victoria Azarenka said she did not believe the same decisions would have been made in a men's match.

Billie Jean King, who won 39 grand slam titles during her career, also came to the defence of Williams.

"Several things went very wrong during the @usopen Women's Finals today," she said on Twitter.

"Coaching on every point should be allowed in tennis. It isn't, and as a result, a player was penalized for the actions of her coach. This should not happen.

"When a woman is emotional, she's "hysterical" and she's penalized for it. When a man does the same, he's "outspoken" & and there are no repercussions.

"Thank you, @serenawilliams, for calling out this double standard. More voices are needed to do the same."

It is not the first time the younger Williams sister has been penalised for verbally abusing officials in the US Open.

In the 2009 semi-final she was on a warning for racket abuse when she launched an outburst at a lineswoman after a foot fault gave Kim Clijsters two match points.

She was penalised a point for unsportsmanlike conduct and Clijsters won the match.

Williams was placed on a two-year probation and fined $175,000 (£135,000), reduced to $82,500 (£63,750) if she met the conditions of her probation.

In the 2011 final Williams shouted "come on" as Sam Stosur went for a return. The point was awarded to the Australian. Williams went on to verbally abuse umpire Eva Asderak and was fined $2,000 (£1,265).