Naomi Osaka has sent her fans into a tailspin after showing off a dramatic new look on social media.
The Japanese star was already the talk of the tennis world after winning her second Australian Open title on Saturday night.
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The triumph was her fourth grand slam title and cemented her status as the new queen of women's tennis.
But its not just her actions on the tennis court that have fans in a frenzy.
The 23-year-old stunned her followers on Friday when she posted a photo on Twitter showing her with long pink hair.
The new look is strikingly different to her usual brown, curly hair, although Osaka didn't clarify whether or not it was a wig.
Referencing a Japanese Manga character, Osaka wrote: "Sakura could never lol."
The photo sent her followers into meltdown, and even Jamaican Olympic legend Usain Bolt took notice.
“U wore it better @naomiosaka lol," he commented.
At time of writing, Osaka's photos had been liked over 68,000 times, with 9000 retweets and over 700 comments.
Naomi Osaka's incredible act for Australian Open ball kid
On Thursday, Osaka gave a brilliant nod to an Australian Open ball girl after noticing her in a photo from Saturday night's final.
Osaka took to Twitter with a repost of the photo, which shows the young girl beaming at Osaka as she celebrates in the foreground.
“Was looking at pics from AO and I just noticed the ball girl in this … hi,” Osaka wrote.
Osaka is being hailed as a double-digit major winner in waiting after soaring into rarefied air with her latest Australian Open triumph.
The Japanese superstar became the first woman since Monica Seles 30 years ago to win her first four grand slam finals and, along with the great Roger Federer, only the third player in the Open era to achieve the feat.
"That's very amazing company," Osaka said.
"I hope that I can have, like, one grain of how their career has unfolded."
Serena and Venus Williams are the only active women's players with more slams than Osaka and three-time Open champion Mats Wilander is convinced the 23-year-old phenom will rack up "10, 11, 12 - minimum" before she calls it quits.
"She's the best hardcourt player we've had in the women's game since Serena was at her best," Wilander said after Osaka beat Jennifer Brady 6-4 6-3 in the Australian Open final.
After adding a second Open title to her 2018 and 2020 US Open crowns, Osaka holds two of the sport's four biggest trophies and could conceivably secure a non-calendar-year grand slam if she wins the French Open in June and Wimbledon in July.
But she's only thinking of grand slam No.5 first.
"I honestly think I'd have better luck on clay because I think last year I didn't play bad at all," Osaka said.
"It's just something that I have to get more used to.
"Definitely there's no reason why I shouldn't do well in those tournaments."
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