The Silicon Valley Classic, where Osaka will play Zheng Qinwen in the first round, is her first event after ending a three-year partnership with Belgian Fissette, who guided her to wins in the 2020 U.S. Open and the Australian Open the following season.
Osaka, 24, said they parted on good terms and all she needed was some fresh energy.
“It was really good times with Wim and he’s a really amazing coach,” she told reporters. “He’s a very ambitious guy. I was getting injured and I’m sure he would have wanted to go to Wimbledon.
“So it was two different mindsets, I would say. But he’s a really cool guy still.”
Osaka’s father, Leonard Francois, previously served as her primary coach until the 2018 season.
“I wanted to bring my dad back because he always makes me think outside the box,” added the former world number one.
“Whenever I think something is really bad he always makes me realise that things are much more positive than they seem. When I get stressed out he starts dancing or something to make me feel better.”
Injuries and poor form have seen Osaka slip to 41 in the world rankings, with the 2021 triumph at Melbourne Park her last title on Tour.
- WPL 2024: Asha’s five-wicket haul helps RCB defeat UP Warriorz in a thriller
- IND vs ENG, 4th Test: Bashir’s exploits, under Nostradamus Stokes, leave India in tatters
- Musheer Khan hits maiden double-century for Mumbai in Ranji Trophy quarterfinal against Baroda
- Ranji Trophy 2023-24 quarterfinals: Anubhav, Kartikeya hand Madhya Pradesh first-innings lead against Andhra on Day 2
- Ranji Trophy 2023-24 quarterfinals: Musheer Khan’s double-century puts Mumbai in strong position on Day 2