Naomi Osaka is optimistic being a "fast healer" will ensure she is pain free when she starts the defence of her US Open title.

Osaka retired from the Western & Southern Open last week after injuring her left knee in Cincinnati.

The world number one on Friday gave a positive update on her condition as she prepares to face Anna Blinkova in the first round at Flushing Meadows.

Osaka said: "Yeah, it's getting better. I have been playing more and longer every day. It's feeling better.

"Luckily I'm a fast healer, so I think it's looking good."

The top seed believes the experience of returning to Indian Wells as defending champion can help her in New York.

"I think going to Indian Wells and kind of learning how defending champion pressure feels, I think it definitely helped me out going into this tournament." said the 21-year-old.

"Because I just feel more loose and comfortable here. I'm not sure if it's because the last couple of months have been kind of turbulent, but definitely I feel really comfortable and I know that, despite everything,

"I play well here every year. So I'm not too worried about that."