Just over two weeks after falling in the second round of the U.S. Open, Naomi Osaka announced that she split with coach Wim Fissette — her partner through the 2020 U.S. Open and 2021 Australian Open titles, the most recent Grand Slams of her career — for a second time.

“4 years, 2 Slams and a whole lot of memories,” Osaka wrote Friday in a post on Instagram. “Thanks Wim for being a great coach and an even greater person, wishing you all the best.”

The pair started working together ahead of the 2020 schedule, according to the Associated Press, and reunited last year when Osaka returned to tennis following her maternity leave in 2022.

Fissette wrote in a separate Instagram post that he felt they were “very close to a breakthrough.”

“When you do the right things and keep hearing from peers you are in the right direction, it’s tough not quite getting it yet,” Fissette wrote. “As the coach, you keep trusting the process, knowing the lessons are getting you closer to the trophies. After the US Open, Naomi decided to move forward with a new path. I accepted it knowing we close this second run with more good memories and gratitude for building her way back. Always wishing the very best for each other and families.”

Osaka had already won two Grand Slam titles by the time Fissette started working with her, and during their first cycle of tournaments, she emerged with a third after winning again in Queens.

Then, she won the Australian Open to start the following year and maintained her ranking as a top-five singles player.

Since stepping away from tennis for a 15-month maternity leave, Osaka hasn’t returned to the pinnacle of the sport, as she currently sits at No. 75 in the singles rankings.

Her upset victory over No. 10-seed Jelena Ostapenko in the opening round of the U.S. Open last month — her first appearance in the tournament since 2022 — marked progress, though, even as she fell to Karolina Muchova in her next match.

And now, Osaka will bank on the coaching change helping her climb the rankings, back toward the area that became a given for her just four years ago, again.

“More so to be part of the comeback journey, seeing her grow as a person, athlete and now mother,” Fissette wrote. “A champion in many ways. We started from zero and developed week by week. In 15 years on tour, this was one of my best years working together with amazing people.”