A controversial cartoon depicting Serena Williams having a tantrum on the court at the US Open lays bare the battles against prejudice that black women face at work every day, according to campaigners.  

Cartoonist Mark Knight denied his portrayal of the former world number one tennis player was racist, and explained he was trying to depict the athlete’s ‘poor’ behaviour when she lost her temper at the umpire following Saturday’s crunch final.

Williams claimed Carlos Ramos had implied she was a cheat and unfairly penalised her in the match she eventually lost to Naomi Osaka.

Knight’s take on the incident, published in the Australian Herald Sun newspaper, showed Williams spitting a dummy onto the floor and stamping on her tennis racquet, as the umpire asked US Open champion Osaka in the background: “Can you just let her win?”

He depicted Osaka, who is of Japanese and Haitian heritage, as a white woman with blonde hair. 

The chief executive of the Women’s Tennis Association, Steve Simon, said he did not feel Ramos was as tolerant to Williams as he would have been to a man, but the Grand Slam record-holder was fined $17,000 (£13,100) for the three code violations.

Campaigners said the portrayal fed into long-standing stereotypes faced by Bame women in the workplace every day. 

Tobi Oredein, a freelance journalist and founder of Black Ballad, a platform which aims to tell the stories of black women, told HuffPost UK: “As a black woman I was disgusted but not surprised when I saw the cartoon. I was disgusted because it is reminiscent of racist caricatures of the past.

“However, it was a reminder that when a black woman, especially a dark-skinned black woman, shows emotions – she is quickly reduced to stereotypes such as the ‘angry black woman’ or likened to animalistic imager,y to say that we aren’t seen or allowed to be seen as full human beings, who can show a range of emotions.”

In a tweet that has been liked more than 6,000 times, US author Charlene Carruthers said: “What happened to Serena happens to black women in the workplace every day.

“Serena was at work. Tennis is her profession. She’s in a profession that doesn’t fully honour or respect her the way she should be. She’s in the ranks of so many black women.”

But others, including Herald Sun editor Damon Johnstone, said the cartoon simply highlighted Williams’ poor behaviour. The paper said it would not apologise for printing it, despite a significant backlash.

According to TUC research, black and minority ethnic women frequently suffer from cultural stereotyping by employers, which results in them having to take jobs at a lower skill level than they are qualified for.

Last year, research conducted by the Guardian and Operation Black Vote found a meagre 3.5% non-white faces at the top of the UK’s leading 1,000+ organisations. Less than a quarter of those BAME positions of power were occupied by women.

Studies by the Prince’s Responsible Business Network show there are more than 20.6m women in the UK’s working age population – of which less than 2.9 million (14%) are black.

Williams is one of a small number of black female tennis players and is the most frequently drug-tested professional woman in the sport.

Freelance journalist Funmi Olutoye told HuffPost UK she thought the cartoon played into negative portrayals of the 14-times Wimbledon champion in the media. 

“Black women are constantly being reminded by society’s beauty standard that we’re too dark-skinned, our hair is not straight enough, our lips are too big, our thighs are too large and that any emotion we feel outside of pure ecstasy is anger,” she said.

The TUC’s probe showed that more than a third of BAME workers in the UK felt they had been bullied, abused or singled out for unfair treatment at work because of their race – and many black women said they were able to relate to this unfair treatment in their own lives.

Journalist Winnie Ngozi Okocha said: “I don’t want to flatten every black woman’s experience to make out that we have one identical story.

“But every black woman I’ve met has lowered their voice or toned down their hairstyles, or decided not to make a complaint in order to avoid being labelled angry or aggressive.

“Even I was called aggressive behind my back by someone in an organisation my previous job worked closely with.”

And on Twitter, Parisian Diva wrote: “Serena Williams standing up for herself triggered me into remembering a time when I refused to accept differing treatment from a boss and the subsequent fallout. Here is the story of a white man who had never met an assertive black woman like me.”

On Tuesday, Knight spoke to No Access Australia and defended the cartoon in the face of signifiant backlash, saying: “I didn’t anticipate this sort of reaction it, you know, once upon a time you would get a terse letter from a reader.

“Now you have the whole world, 80 million people piling on you.

“I didn’t anticipate that with this cartoon which was basically just a cartoon about a sportswoman having a hissy fit on centre court at the US Open.”

“The cartoon was basically, I watched the US Open, I saw the world number one tennis player spit the dummy on centre court and I thought ‘oh well that’s newsworthy, I’ll draw a cartoon about that.’,” he added.

“So I drew Serena having a tantrum. But unfortunately the cartoon has been I guess picked up and distorted. It’s been tipped into US racial politics and now I’m unfortunately embroiled in that.”