Four-time grand slam champion Naomi Osaka has announced she has split with coach Patrick Mouratoglou after less than a year.

Osaka hired the long-time coach of her idol Serena Williams shortly after firing Wim Fissette following her second-round exit at last year’s US Open.

But the signs were ominous when Mouratoglou was absent from the DC Open this week.

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“Merci Patrick,” Osaka said.

“It was such a great experience learning from you. Wishing you nothing but the best.

“You are one of the coolest people I’ve ever met and I’m sure I’ll see you around.”

She will now head to Toronto this week and then Flushing Meadows for the final grand slam of 2025 with a new-look team.

The US Open, an event she has won twice, begins in New York on August 24.

Osaka initially hesitated partnering up with Mouratoglou, fearful that Williams had elevated his reputation.

“I think the fact that he was Serena’s coach for me made me want to avoid him just because his persona is so big,” she said last year.

“Like, this isn’t rude because I found out it’s not true, but I didn’t know if he was a good coach or he coached Serena.

“Then I met him, talked to him, worked with him on the court. He absolutely is a really good coach. I’m really glad that he’s taking this project on as well.”

The former world No.1 is currently ranked 51st and has a 21-11 record this season.

She hasn’t been past the third round at a grand slam tournament since winning the 2021 Australian Open.

Osaka later took time out to give birth to her daughter, whose birthday coincided with her defeat at Wimbledon earlier this month.

“Honestly, right now I’m just really upset,” she said after the match.

“I’m just gonna be a negative human being today. I’m so sorry. I have nothing positive to say about myself, which is something I’m working on.

“It was my daughter’s birthday. I was happy about that this week. Other than that, today, I’m just constantly replaying the match.

“I think if I look back on it, I can be happy with how I played. I started getting a lot more comfortable on grass.

“It’s because I actually thought I could play well in general. Not saying I didn’t play well, but make a deep run here. I wanted to do better than I did before. Also, I felt like I was trying so hard. I low-key busted a vein in my hand.

“I feel like, while I still have the opportunity to try to (compete), I want to. Even though I get very upset when I lose, but I think that’s my competitive nature.”

In tears after being eliminated from the French Open in May, having lost to 10th seed Paula Badosa in a nightmare first-round match-up, Osaka was asked to compare that to the Wimbledon defeat.

“I think in Paris ... when I sat here, I was very emotional. Now I don’t feel anything,” she said.

“I guess I prefer to feel nothing than everything.”

The Wimbledon press conference went viral where it was splashed across social media and various media outlets.

But the 27-year-old later fumed about how she was portrayed.

“Bro ... why is it every time I do a press conference after a loss the ESPNs and blogs gotta clip it and put it up,” she said on X (formerly Twitter).

“WTF, why don’t they clip my press conferences after I win? Like, why push the narrative that I’m always sad?

“Sure I was disappointed a couple hours ago, now I’m motivated to do better. That’s human emotions. The way they clip me I feel like I should be fake happy all the time.”

- with AP