Naomi Osaka, of Japan, is hugged by Serena Williams after Osaka defeated Williams in the women's final of the U.S. Open tennis tournament. Photo / AP
Serena Williams has been fined a total of NZ$25,700 for three code violations during the US Open final.
The tournament referee's office docked Williams US$10,000 for 'verbal abuse' of chair umpire Carlos Ramos, US$4,000 for being warned for coaching, and US$3,000 for breaking her racket.
The money comes out of her prize money of NZ$2.7m (US$1.85m) as the runner-up.
Williams' furious outburst at umpire Carlos Ramos overshadowed her 6-2 6-4 final defeat by Naomi Osaka at Flushing Meadows on Saturday.
Initially unhappy about being penalised for Patrick Mouratoglou coaching from from the stands, Williams was then given a point penalty for smashing her racket before Ramos took a game away from her after she called him a 'thief'.
The American tennis great stated afterwards that it was 'sexist' for her to have been penalised a game.
During her post-match press conference, the 36-year-old said: "I can't sit here and say I wouldn't say he's a thief, because I thought he took a game from me.
"But I've seen other men call other umpires several things. I'm here fighting for women's rights and for women's equality and for all kinds of stuff.
"For me to say 'thief' and for him to take a game, it made me feel like it was a sexist remark. He's never taken a game from a man because they said 'thief'. It blows my mind.
"I just feel like the fact that I have to go through this is just an example for the next person that has emotions, and that wants to express themselves, and wants to be a strong woman.
"They're going to be allowed to do that because of today. Maybe it didn't work out for me, but it's going to work out for the next person."
Tennis legend Billie Jean King, who won 12 Grand Slam singles titles, including four US Opens, was among those who jumped to back Williams as the row escalated.
King said on Twitter: "Several things went very wrong during the Women's Finals today.
"Coaching on every point should be allowed in tennis. It isn't, and as a result, a player was penalized for the actions of her coach. This should not happen."
"When a woman is emotional, she's 'hysterical' and she's penalized for it. When a man does the same, he's 'outspoken' and there are no repercussions. Thank you, @serenawilliams, for calling out this double standard. More voices are needed to do the same."
Meanwhile, Mouratoglou admitted to ESPN that he had sent Williams a signal during the match — but claimed every coach does it.
Responding, Williams said: "I literally just heard that too. I just texted Patrick because we don't have signals, we've never discussed signals. I want to clarify myself what he's talking about. I wasn't being coached."
The row has completely overshadowed Osaka's maiden Grand Slam victory. Through all the chaos, the 20-year-old kept her nerve, and served it out with remarkable sangfroid despite the mayhem in the Arthur Ashe Stadium.
However, she was left in tears as her triumph was met with a chorus of boos, even if not directed at her.
The whole incident had been reminiscent of Williams's loss of control on the same arena when she threatened to ram a ball down a line judge's throat in 2009.