"Oh my god, I don't even know (where that performance came from) ... honestly like, what is my life?” Gauff laughed on court.
"Two years ago, I lost first round in juniors. And now I'm here. This is crazy. Oh my gosh, I'm on Rod Laver Arena, like, I can't believe this (laughter)."
She later added in press: "Definitely (this victory) has to be somewhere around the top. I thought I played really well today and I was pretty composed and really calm.
"(This time I was ready for) the pace of her ball. She definitely plays faster than most players. I think at US Open I wasn't really prepared for that. And today I definitely showed that I worked on that in the off-season."
Osaka arrived at her press conference shortly after departing the stadium, a little shell-shocked.
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“To do stuff differently, I would have had to expect that she played like that, but I wasn't really,” Osaka admitted.
“Her serve is way better than I played her last year.
“You don't want to lose to a 15-year-old, you know. But I guess that's for me, like, a reality check. It doesn't really matter the age of the opponent. Of course she deserves to be here. She played her matches. I just have to work harder.
“I love her, but I don't like this feeling of losing to her.”