The Women’s Tennis Association has backed Serena Williams' claim of sexism in the way she was treated by umpire Carlos Ramos during the US Open final.

Williams was warned for coaching, then docked a point for smashing a racket before Ramos penalised her a game after she called him a liar and a thief.

That left the 23-time grand slam singles champion one game from defeat and in tears, with Naomi Osaka clinching her first slam title shortly afterwards.

Williams argued on court with tournament officials, claiming she was being treated differently to how a man would be in such circumstances, a theme she continued in her press conference.

The American has received a lot of support from current and former players, and on Sunday night, moments after Novak Djokovic won the men's title, WTA chief executive Steve Simon released a statement.

Simon said: "Yesterday's US Open final resulted in the crowning of a deserving new champion, Naomi Osaka. The WTA applauds Naomi for her tremendous accomplishment.

"Yesterday also brought to the forefront the question of whether different standards are applied to men and women in the officiating of matches.

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

US Open champion Naomi Osaka

Simon also called for coaching to be allowed during grand slam matches. Ramos penalised Williams after seeing her coach, Patrick Mouratoglou, making a hand gesture. The Frenchman later admitted he was trying to coach his player.

Simon continued: "We also think the issue of coaching needs to be addressed and should be allowed across the sport. The WTA supports coaching through its on-court coaching rule, but further review is needed."

Following the match, the United States Tennis Association, which runs the tournament, put out a statement from its president, Katrina Adams, hailing Williams for her "class" and "sportsmanship".

Adams also claimed there are double standards in terms of how umpires treat women and men.

She said: "We watch the guys do this all the time, they're badgering the umpire on the changeovers, nothing happens. There's no equality."

Bizarrely, Adams also claimed that Williams had not expected her exchanges with Ramos to be filmed despite taking place in the middle of a grand slam final.

Djokovic had sympathy for Williams in terms of the sanctions she was given but does not agree that women are treated differently from men.

He said: "I love Serena, first of all. I really felt for her yesterday. Tough thing for a chair umpire to deal with, as well. We have to empathise with him. Everyone was in a very awkward situation. A lot of emotions. Serena was crying. Naomi was crying. It was really, really tough.

"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. 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."