15-year-old Coco Gauff has knocked out Australian Open defending champion, Naomi Osaka on Friday.

The American teenager defeated the world No. 3 with  6-3 6-4 in straights sets at The Rod Laver Arena to claim one of the biggest wins of her young career and book her place in the fourth round in Melbourne.

Speaking after the game, the teen sensation said, “Two years ago, I lost in the first round at juniors and now I’m here!” 

What is my life? Oh my gosh, Two years ago I lost first round in juniors, and now I’m here. This is crazy,” said Gauff, who is still doing schoolwork online.

“I was just telling myself one point at a time and keep fighting because you never know what happens on this court. I’m on Rod Laver Arena, I can’t believe this.

The win came after Gauff defeated tennis legend, Venus Williams, in the first round of the Australian Open four days ago.

Gauff will now face either American Sofia Kenin or Shuai Zhang of China in the next round.