US Open 2018: Naomi Osaka stuns Serena Williams to become Japan's first grand slam champion

The 20-year-old won her first grand slam title in her first final as she managed to keep her cool whule witnessing a remarkable Williams meltdown on the other side of the net.

The headlines were supposed to be about Williams' bid for a record-equalling 24th grand slam title and Osaka trying to become Japan's first slam winner, but instead an argument with umpire Carlos Ramos that escalated dominated the match.

Williams was furious when she was given a coaching violation early in the second set after a hand gesture from her coach Patrick Mouratoglou.

She was then docked a point for a second violation when she smashed her racket after dropping serve at 3-3. Continuing her argument with Ramos at the change of ends, Williams accused him of being a thief for taking a point away from her.

Ramos gave her a third violation, which resulted in a game penalty, putting Osaka 5-3 ahead. A tearful Williams argued her case with tournament officials but, although she held serve in the next game, Osaka served out the victory 6-2 6-4.

The presentation ceremony began with more booing from the crowd before a tearful Williams said, to wild cheers: "I don't want to be rude. I don't want to do questions.

"I just want to tell you guys she played well. Let's make this the best moment we can and get through it and give credit where credit is due. No more booing. Let's be positive."

Osaka was also in tears, and said: "I know everyone was cheering for her and I'm sorry it had to end like this. I just want to say thank you for watching the match.

"It was always my dream to play Serena in the US Open finals. I'm really glad I was able to do that."

More Serena reaction

After Osaka hit the final serve, Williams warmly embraced her young opponent, who grew up idolising the American, then refused to shake Ramos' hands, instead giving him a final verbal volley.

Afterwards Mouratoglou admitted to ESPN that he was sending Williams a signal, 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."

Williams was most unhappy about the third violation after she accused Ramos of being a thief for taking the point off her.

Becoming increasingly emotional in a generally composed press conference, asked what she would change if she could, 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."

A statement from the WTA read: "There are matters that need to be looked into that took place during the match. For tonight, it is time to celebrate these two amazing players, both of whom have great integrity.

"Naomi is a deserving champion and Serena at all times plays with class and makes us proud."

It is not the first time the 36-year-old has run into trouble with officials at Flushing Meadows. In a semi-final against Kim Clijsters in 2009, she was penalised for threatening a line judge and fined.

Two years later, during a final loss to Sam Stosur, Williams called umpire Eva Asderaki "a hater" and "unattractive inside" for calling a hindrance penalty against her.

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