Osaka has won only one title while collaborating with Mouratoglou – more precisely the Saint-Malo WTA 125 – really too little for a champion of her caliber, who has made the recent history of women's tennis by becoming a point of reference for all her rivals.

Naomi Osaka and coach Patrick Mouratoglou are done working together after less than a year, the four-time Grand Slam champion announced Sunday on social media. “Merci Patrick,” Osaka began her post, with a photo of her hitting a practice serve while he stands nearby.

The four-time major champion announced that she had parted ways with coach Patrick Mouratoglou following middling results.