Naomi Osaka was fined $15,000 by Grand Slam organisers for skipping a news conference following her first-round win at the French Open on Sunday, and was also warned of possible expulsion from Roland Garros and future majors if she fails to meet her media commitments.
In the run up to the claycourt major, the world number two announced she would boycott news conferences while in Paris to raise awareness of players' mental well-being, saying the nature of questions from journalists is like 'kicking a person when they are down'.
Osaka started her French Open campaign with a 6-4, 7-6(4) win over Romanian Patricia Maria Tig and then snubbed the post-match news conference, although the four-time Grand Slam champion did hold a court-side interview immediately after the contest.
The board of the four Grand Slams said in a statement on Sunday that the French Open organisers had asked Osaka to reconsider her position and tried unsuccessfully to speak with her to resolve the matter.
"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 dialogue," 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."
"Naomi Osaka today chose not to honour her contractual media obligations. The Roland Garros referee has therefore issued her a $15,000 fine."
Osaka's management did not immediately respond to a request for comment.
The 23-year-old Japanese player, who lives in Florida, has never made it past the third round at Roland Garros and arrived in Paris having played only three matches on clay this season after early defeats in Madrid and Rome.
Osaka, who according to sports business website Sportico earned $55.2 million over the past 12 months, has previously used her platform and considerable media attention to highlight issues of police violence and racial inequality.
While announcing her decision on Twitter to boycott news conferences she said she hoped the "considerable amount" that she expected to forfeit as fines would go towards a mental health charity.
Rafael Nadal, a 20-time Grand Slam winner, and women's world number one Ash Barty have said they believe players have a duty to address the media.
Seven-time Grand Slam singles champion Mats Wilander said on Sunday that Osaka should not play tournament tennis until she is ready to take part in post-match news conferences.
"We have advised Naomi Osaka that should she continue to ignore her media obligations during the tournament, she would be exposing herself to possible further Code of Conduct infringement consequences," the board of the four Grand Slams added.
"As might be expected, repeat violations attract tougher sanctions including default from the tournament ... and the trigger of a major offence investigation that could lead to more substantial fines and future Grand Slam suspensions."
The board said it would be unfair to other players if Osaka refuses to face the press while others honour their commitments.
"We will see how everything will end up," two-time Wimbledon winner Petra Kvitova said after her win in the opening round.
"But me personally, I was always trying to follow the rules and be fair not only on the court but off the court as well. Now it's up to them to decide what's going to be."
Osaka showed no signs of being distracted by the issue during her opening match on a sun-bathed Philippe Chatrier court, however.
Asked in her courtside interview about how she adapts her game to the surface, Osaka said: "It's a work in progress. Hopefully the more I play the better I play."
"I'm really glad that I won. It's a beautiful court. I've only played two matches here (on Philippe Chatrier), one before the roof and one now, so hopefully I'll keep it going."
Osaka, who missed last year's tournament due to a hamstring problem, was not keen on engaging in long rallies and seemed too powerful against the 63rd-ranked Tig.
She stamped her authority on the match early with a 5-2 lead but needed a second break of serve after the Romanian staged a late fightback.
Tig saved a break point and a match point to take the second set into a tiebreaker before Osaka sealed it with a backhand winner to set up a second round meeting with another Romanian in Ana Bogdan.
