Four-time Grand Slam champion Naomi Osaka hit back at a fan on social media that she says called her a "fluke" just a day after she was forced to retire from a match at the China Open due to a lower back injury. 

Osaka, who returned to the sport this year after an 18-month hiatus during which she gave birth to her daughter Shai, posted a rant on Instagram calling out the internet troll by reminding them of her decorated resume. 

Naomi Osaka returns a shot

Naomi Osaka returns a shot to Coco Gauff in a women's singles match for the China Open at the National Tennis Center in Beijing, Tuesday, Oct. 1, 2024. (AP Photo/Achmad Ibrahim)

"I just saw someone call me a fluke. How is it possible to be a fluke with 4 Grand Slams, lighting the Olympic torch, beating multiple top 20 opponents and being close to top 50 the year after giving birth?" 

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She continued, "FOH, you couldn’t even touch one of my accomplishments with your fingernail." 

In the post shared to her Instagram Stories, Osaka added, "Did I lieeeee????" 

Osaka, 26, won her first career Grand Slam in 2018 when she defeated Serena Williams at the U.S. Open, dropping just one set the entire tournament. She would win in New York again in 2020 and win two more major titles at the Australian Open in 2019 and 2021. 

Naomi Osaka looks on

Naomi Osaka walks onto the court for her match against Karolina Muchova at the U.S. Open at Billie Jean King National Tennis Center.  (Geoff Burke-USA Today Sports)

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But Osaka’s return this year hasn’t been without its struggles. 

She lost in the first round of the Australian Open in January and exited the French Open and Wimbledon after the second round. Her performance at the 2024 Paris Olympics wasn’t much better, with a first-round loss to Germany's Angelique Kerber. 

Following a second round loss at the U.S. Open, Osaka announced that she would be parting ways with Wim Fissette, who coached her to two of her Grand Slam titles. 

Naomi Osaka reacts

Japan's Naomi Osaka reacts during a play against Italy's Lucia Bronzetti during the China Open in Beijing, Wednesday, Sept. 25, 2024. (AP Photo/Ng Han Guan)

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She picked up her first win with new coach Patrick Mouratoglou at the China Open last week, but was forced to retire from her Round of 16 match against Coco Gauff on Tuesday due to a lower back injury. 

The Associated Press contributed to this report. 

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