Naomi Osaka says she still needs to improve her game despite breezing into the last 16 of the U.S. Open with a virtually flawless victory over Aliaksandra Sasnovich of Belarus on Saturday.The Japanese 20-year-old said she had yet to play the best tennis of her career after making just three unforced errors in a 6-0, 6-0 drubbing of her third-round opponent."I feel like I can always do something better. I feel like that's one really good thing about me but also something negative, because I'm never satisfied," Osaka said.The match started competitively, with Osaka defending four break points…READ FULL ARTICLE
