World No. 1 Naomi Osaka has called time on her 13-month relationship with coach Sascha Bajin, once the former hitting partner of great Serena Williams, despite their partnership yielding success in the last two Grand Slams.
Osaka won her first WTA title at the BNP Paribas Open, last March, following which she went on to clinch 2018 US Open title and 2019 Australian Open.
She also thanked Bajin and wished him "all the best in the future".
"Thank you Naomi. I wish you nothing but the best as well", Bajin said.
Osaka hired Bajin ahead of the 2018 WTA season and the pair didn't take long to click on court. "Thank you for letting me be part of this", he said.
Osaka will next appear in Dubai Duty Free Tennis Championships, beginning next week.
Osaka enjoyed a remarkable rise up the world rankings after first linking up with Bajin in the 2017 off-season.
Osaka, who withdrew from this week's Qatar Open due to a back injury, has not yet announced a replacement for Bajin.
The 21-year-old beat Petra Kvitova in three sets in the Australian Open final on January 26.
Osaka is the first player from Asia to grace the top of the women's or men's world tennis rankings.