Naomi Osaka tells a story.
It is from Florida, where the world's best young tennis players congregate and compete.
Osaka, aged about 10, was getting ready for a match at the prestigious Orange Bowl tournament.
Preparing within earshot of her Japanese opponent, Osaka overheard her conversation.
"And they didn't know that I was listening or that I spoke Japanese.
"Her friend asked her who she was playing, so she said 'Osaka'. And her friend says, 'Oh, that black girl. Is she supposed to be Japanese?' And then the girl that I was playing was like, 'I don't think so.