Tennis: Naomi Osaka opens up on Serena Williams' US Open umpire confrontation

Naomi Osaka with the US Open trophy after defeating Serena Williams. AP

Naomi Osaka has revealed the mixed emotions she felt after defeating Serena Williams to win her first Grand Slam title at the US Open last month, describing the experience as "bittersweet".

Osaka's victory was overshadowed by Williams' confrontation with umpire Carlos Ramos, so much so that during the trophy presentation she was moved to tears and could barely raise a smile.

Speaking at the China Open where she had just beaten Kazakhstan's Zarina Diyas 6-3, 6-4 in the first round, Osaka opened up about how emotionally draining the US Open final had been.

"There's a lot of stuff I want to say about, like, how I felt and whatever," she said. "But for me, I don't know, I don't know.

"The memory of the US Open is a little bit bittersweet. Like right after, the day after, I really didn't want to think about it because it wasn't necessarily the happiest memory for me."

"I mean of course I'm happy that I won a Grand Slam. I don't think there's anything that can take away from that. But I don't know. I feel like not that when I look back on it that it's a bad memory but I feel like it was so strange, I just don't want to think about it.

"I wanted to just push it to the side. Then I played Tokyo. For me, Tokyo was a way to take my mind of it. I think that's why I did well.

"I'm still trying to take my mind off of it a little bit. I guess hopefully I can do well here, too."

Having reached the final in Tokyo last month, the No 8 seed Osaka will continue her Beijing Open campaign with a second-round match against Danielle Collins.