The 15-year-old sensation prevailed 6-3, 6-4 over the Japanese champion, who gave her opponent a huge hug at the net after her latest epic achievement.
Gauff won just three games against Osaka during their meeting at the US Open but ruthlessly exposed the sloppy tennis from the former No 1.
“I don’t know where that came from,” a shocked Gauff said when reacting immediately to her latest achievement. “Honestly, like, what is my life? two years ago I lost first round in juniors and now I’m here! I was telling myself one point at a time and keep fighting. You never know what happens on this court.
“I love it down here, oh my gosh! Thank you guys from the bottom of my heart. I’m on the Rod Laver Arena! I can’t believe it!
“I’ve walked past Rod Laver a couple of times in the hallway but I’ve never met him- if he sees this, tell him we can set up a meeting sometime. I need a selfie for Instagram!”
When asked what she will do about her schoolwork after extending her stay in Melbourne, Gauff promised to work on it tomorrow.
“I’ll probably do homework tomorrow because I want to go to sleep tonight,” Gauff said.
“My teachers are giving me some time because considering the circumstances... they’re letting me submit some assignments late, so that’s nice!”