Ramos has been accused of specifically targeting Williams for the coaching violation, although the Portuguese umpire has a reputation of being a strict enforcer of the rules.
Williams was unhappy at the violation call and complained to Ramos she hadn't taken any signals.
"The Sept 10 cartoon not only exudes racist, sexist caricatures of both women, but Williams' depiction is unnecessarily sambo-like", echoed the National Association of Black Journalists, which described the drawing as "repugnant".
Tennis legend Billie Jean King has said Serena Williams was "totally out of line" with her behaviour during the US Open final, but also suggested that umpire Carlos Ramos could have handled the situation better.
The governing body's support for Ramos came after the WTA, which operates the women's tour, was critical of the way things went between him and Williams in NY. He has also been on the chair for the women's singles finals at three of the four majors - the French Open in 2005, Wimbledon in 2008 and at Flushing Meadows on Saturday. "At the same time, it is important to remember that Mr. Ramos undertook his duties as an official according to the relevant rule book and acted at all times with professionalism and integrity".More news: Track Hurricane Florence as it heads for the East Coast
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The Women's Tennis Association (WTA) and United States Tennis Association (USTA) were among those to back Williams in the aftermath of her outburst.
Williams' heated exchanges with an umpire at the tournament final this week have stirred the tennis world. And if WTA players do feel strongly that umpires treat them more harshly then men, then this needs to be investigated.
While Osaka won the match fair and square, Williams pointed out that male players like John McEnroe had much bigger tantrums with little penalty.
Andy Murray kicked a ball at an umpire's head during a 2016 match, but did not get a code or point penalty.
Williams was issued a warning for coaching, something her coach sitting in the stands, Patrick Mouratoglou, admitted to doing. Debates have raged about whether chair umpire Carlos Ramos unfairly penalized Williams. Williams is seen with bushy hair and stomping on an already broken tennis racket. "There is a huge double standard for women when it comes to how bad behavior is punished - and not just in tennis", Navratilova said.
"The WTA believes that there should be no difference in the standards of tolerance provided to the emotions expressed by men v women and is committed to working with the sport to ensure that all players are treated the same".