By Ben Morse, CNN

(CNN) -- Tennis star Naomi Osaka said Monday she is withdrawing from the French Open after refusing to speak to the media at the grand slam.

The four-time major winner posted a statement on Twitter saying she was pulling out so that "everyone can get back to focusing on the tennis going on in Paris."

Last Wednesday, citing mental health reasons, Osaka posted on social media she would not participate in any news conferences during the French Open, hoping that any fines she incurred would go toward a mental health charity.

Following her straight set victory on Sunday, Osaka was fined $15,000 for not talking to the media, Roland Garros announced in a statement.

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"This isn't a situation I ever imagined or intended when I posted a few days ago," Osaka said in her statement.

"I think now the best thing for the tournament, the other players and my well-being is that I withdraw so that everyone can get back to focusing on the tennis going on in Paris.

"I never wanted to be a distraction and I accept that my timing was not ideal and my message could have been clearer. More importantly I would never trivialize mental health or use the term lightly.

"The truth is that I have suffered long bouts of depression since the US Open in 2018 and I have had a really hard time coping with that.

"Anyone that knows me knows I'm introverted, and anyone that has seen me at the tournaments will notice that I'm often wearing headphones as that helps dull my social anxiety.

"Though the tennis press has always been kind to me (and I wanna apologize especially to all the cool journalists who I may have hurt), I am not a natural public speaker and get huge waves of anxiety before I speak to the world's media.

"I get really nervous and find it stressful to always try to engage and give you the best answers I can. So here in Paris I was already feeling vulnerable and anxious so I thought it was better to exercise self-care and skip the press conferences.

"I announced it preemptively because I do feel like the rules are quite outdated in parts and I wanted to highlight that. I wrote privately to the tournament apologizing and saying that I would be more than happy to speak with them after the tournament as the Slams are intense.

"I'm gonna take some time away from the court now, but when the time is right I really want to work with the Tour to discuss ways we can make things better for the players, press and fans."

Following her decision to opt out of media duties last week, the French Open was criticized for posting a tweet -- which it has since deleted -- with photos of Rafael Nadal, Kei Nishikori, Aryna Sabalenka and Coco Gauff engaging in media duties with the caption: "They understood the assignment."

Four-time grand slam doubles winner Rennae Stubbs tweeted: "This is some serious shade from Roland Garros & the FFT (French Tennis Federation).

"I understand your attempt at making a point but this isn't a good look. I mean these particular players are a great look for tennis but making a player feel guilty & humiliating her is NOT a good look for a tennis fed."

After her victory over Romania's Patricia Maria Tig in straight sets on Sunday, the 23-year-old Osaka did not speak to the media, an action she was fined for.

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Roland Garros said it asked Osaka "to reconsider her position and tried unsuccessfully to speak with her to check on her well-being, understand the specifics of her issue and what might be done to address it on site."

"Following the lack of engagement by Naomi Osaka, the Australian Open, Roland-Garros, Wimbledon and the US Open jointly wrote to her to check on her well-being and offer support, underline their commitment to all athletes' well-being and suggest dialog on the issue," the statement read. "She was also reminded of her obligations, the consequences of not meeting them and that rules should equally apply to all players."

Organizers said that repeated violations could lead to tougher sanctions including default from the tournament.