The former world number one was fined by the US Tennis Association after calling judge Carlos Ramos a “liar” and a “thief”.

Image:Serena Williams gestures to umpire Carlos Ramos at the US Open

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.”