Other US media pointed out that Osaka was portrayed as petite and feminine with blonde straight hair - in real life she has dark curly hair with blonde streaks and is taller than Williams.
"I don't understand from where he's coming with that statement", said Djokovic, suggesting this was the first he has heard of umpires failing to treat men and women equally.
Knight said he had received death threats against his family since it was published, forcing him to suspend his Twitter account.
The detractors included author JK Rowling, who said: "Well done on reducing one of the greatest sportswomen alive to racist and sexist tropes and turning a second great sportswoman into a faceless prop".
'It had nothing to do with gender or race, ' he said in the publication.
Ramos is back in the umpire's chair this weekend when Croatia host the United States in a Davis Cup tie in Zadar and USA captain Jim Courier said of the Williams incident: "It's been polarized and in some ways politicized". Eventually, Williams called Ramos "a thief", drawing the third violation for "verbal abuse" - and costing her a game, putting Osaka ahead 5-3.
Osaka says her sights are now set on making the season-ending WTA Finals in Singapore.
"Serena Williams has part of it right". Williams lost, 6-2, 6-4, with the loss setting off widespread debate over potential sexism and double standards in tennis.
"But in her protests. she also got part of it wrong".
Williams, who has since been fined $17,000 by the United States Tennis Association for the violations, vigorously disputed each of them during the match.
"I think the umpire did what was within his rights", Murray told BBC Sport on Thursday ahead of the U.K.'s Davis Cup. According to the Telegraph, such violations have risen since 2009 among women after the Women's Tennis Association began allowing a coach to visit his or her player at one changeover per set. She briefly disputed that ruling, saying cheating "is the one thing I've never done, ever" - although afterward, her coach, Patrick Mouratoglou, acknowledged he was trying to send Williams a signal.