Mari Osaka, the sister of Australian Open champion Naomi, has announced her sad retirement from tennis at the age of 24.
The elder Osaka made the heartbreaking announcement on Tuesday, saying her tennis career was a journey she didn't enjoy.
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"I am retired from playing tennis," she wrote on Instagram.
"It was a journey which I didn't enjoy ultimately but I'm grateful for all the memories and support I've gained and received over the years from the sport.
"I'm moving on now so you can look forward to new fun projects upcoming in the future."
Ranked 340th in the world, Osaka has played most of her career on the ITF circuit.
She reached her highest ranking of 280 in 2018.
Naomi Osaka, currently ranked World No.2, has previously spoken about how Mari was the better player when they were younger.
"Up until I was 15 she was 6-0-ing me, ridiculous," Naomi told The New York Times.
"I don't know what happened, maybe finally something clicked in my head, but for sure she was beating me.
"In the win-loss record, she's up by like a million or something."
Naomi said it was her dream to be able to play with her sister on the WTA tour.
"For me it would be a dream," she said.
"Because I don't really talk to that many people, and she's the nicer one in this relationship. It would definitely mean a lot."
Mari Osaka only played one match in 2021, losing to Sarah Hamner in the first round of qualifying for an ITF event in Georgia in January.
Naomi Osaka destined for tennis greatness
Meanwhile, Naomi 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 with victory at Melbourne Park last month.
Margaret Court also accomplished the feat in the early 1960s, as did Roger Federer before going on to rack up a record 20 men's grand slam singles crowns.
Ominously for Osaka's rivals, not even legends Serena and Venus Williams, Steffi Graf, Martina Navratilova, Chris Evert nor Billie-Jean King managed to win their first four major finals.
"I think she has 10 grand slams in her, minimum, I really do," Wilander said on Eurosport.
"She moves really well, she's so strong and doesn't look as if she can get hurt very easily.
"She's very subdued when she wins which means, I think, she wants to win more. Everything speaks for her winning at least 10 majors.
"She says she's gonna take it in fives. Certainly she's gonna get to five. I would think she's up there on 10, 11, 12 minimum.
"She's the best hardcourt player we've had in the women's game since Serena was at her best.
"She hasn't lost a grand slam final and hasn't lost in the second week of a slam so I don't know if she feels pressure."
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