LONDON -- Former world No. 1 Naomi Osaka has announced that she is no longer working with coach Wim Fissette.
Osaka had expressed frustration with her recent results after a second-round exit at the US Open just over two weeks ago. She is currently ranked No. 75.
Osaka, 26, won two of her four Grand Slam titles while working with the Belgian coach. Those were the 2020 US Open and the 2021 Australian Open.
It's the second time Osaka and Fissette have parted ways.
In an Instagram story late Friday, the Japanese player wrote: "4 years, 2 Slams and a whole lot of memories. Thanks Wim for being a great coach and an even greater person, wishing you all the best."
Fissette began working with Osaka shortly before the start of the 2020 season. They had split in summer 2022 before teaming up again last year when Osaka returned to training following maternity leave.
"In 15 years on tour, this was one of my best years working together with amazing people," Fissette wrote in an Instagram post Saturday. "From every defeat, we worked harder and better and grew a lot. We were very close to a breakthrough."
After the US Open, Osaka "decided to move forward with a new path," he added. "I accepted it knowing we close this second run with more good memories and gratitude for building her way back."
At Flushing Meadows, Osaka lost 6-3, 7-6 (5) to Karolina Muchova in the second round. Afterward, she said: "It's a little rough, because I do take these losses really personally. It's like a dramatic word, but I feel like my heart dies every time I lose."
Fissette previously worked with players such as Victoria Azarenka, Kim Clijsters, Simona Halep and Angelique Kerber.