Naomi Osaka says she still does not feel like herself on court eight months into her comeback season after a maternity break. The four-time grand slam title winner is also puzzled at her lack of power and accuracy.

The 26-year-old was beaten by Ashlyn Krueger in the second round of qualifying for the Cincinnati Open, the latest setback in a patchy run of form heading into the final grand slam tournament of the year at the US Open, which starts on 26 August. Osaka triumphed at Flushing Meadows in 2018 and 2020.

“My biggest issue currently isn’t losses though, my biggest issue is that I don’t feel like I’m in my body,” Osaka wrote on Instagram. “It’s a strange feeling, missing balls I shouldn’t miss, hitting balls softer than I remember I used to. I try to tell myself: ‘It’s fine, you’re doing great. Just get through this one and keep pushing,’ mentally it’s really draining through.

“Internally, I hear myself screaming: ‘What the hell is happening?!’”

Osaka returned to action in January after a 15-month break during which she gave birth to her daughter. Now ranked 90th in the world, her best results have been runs to the quarter-finals at Doha and ’s-Hertogenbosch.

“I’ve played a handful of matches this year that I felt like I was myself and I know this moment is probably just a small phase from all the new transitions (clay, grass, clay, hard), however, the only feeling I could liken how I feel right now to is being postpartum,” Osaka said.

“That scares me because I’ve been playing tennis since I was three, the racket should feel like an extension of my hand.”

Osaka said she did not understand why everything about her game felt “almost brand new” again. “This should be as simple as breathing to me, but it’s not. I genuinely did not give myself grace for that fact until just now.”

Despite her struggles, Osaka said she loved putting in the work each day and “eventually having the opportunity to get to where you want to be”.