Osaka's time with Mouratologou followed an up-and-down sequence of promising signs and frustrations with either injury or close-run defeats.

Naomi Osaka is making a major change at the start of the North American hard-court swing as the former world No. 1 decided to call time on her partnership with coach Patrick Mouratoglou.

Naomi Osaka has ended her 10-month coaching partnership with Patrick Mouratoglou, a French coach of Greek descent, after inconsistent results. The four-time Grand Slam champion announced the split on Instagram,