Teenager Noskova stuns top seed Swiatek at Australian Open

The Pole, more accustomed to breezing past opponents with the odd "bagel" or 6-0 scoreline thrown in, had struggled in Melbourne, enduring a first-set tiebreak in her opener against Sofia Kenin before fighting back from the brink of defeat to oust Danielle Collins.

Things were looking up for her after a strong opening set but Noskova dug deep to become the first teenager to defeat the top-ranked player at the Australian Open since Amelie Mauresmo toppled Lindsay Davenport in 1999.

"I'm speechless, I knew it was going to be an amazing match with the world number one and such a player, but I didn't really think it would end up like this," said Noskova.

The emotional victor crouched to the floor and put her hands over her face when the big moment came and buried her head in her towel later and cried.

"I'm just really glad to get through this round," she added.

Noskova, 19, emerged as a tricky third-round opponent with three top-10 wins under her belt, but Swiatek looked in no mood to be dragged into another dogfight as she broke in the sixth game and held to love in the next to take charge.

The 22-year-old barely let the intensity drop after taking the first set as she forced Melbourne Park debutant Noskova into uncomfortable positions in the second by working the angles and launching big forehands.

But Noskova held firm, responding with explosive hitting of her own and breaking en route to levelling up the contest.

"I felt like I had everything under control until she broke me in the second set," Swiatek said.

"I had couple of chances to break her in second set and I didn't use them. That's a shame.

"She was proactive. I wanted to do that later in the next games. Sometimes I was rushing it. I wasn't playing with my intuition and naturally.

"I guess I'll have to work on stuff to feel more comfortable next year."

World number 50 Noskova heaped the pressure on the four-time major champion to take a 2-1 lead in the decider.

Swiatek looked to have composed herself during a brief pause in play as doctors attended to a sick supporter in the crowd and broke back, but Noskova did not relent and got her nose in front again to close out the match on serve and complete a huge upset.

"I was shaking a little," Noskova said about serving for the victory. "I didn't hit two first serves which was not the best start for me but I pulled out an ace."

Swiatek said she had been more stressed at Melbourne Park than in other tournaments, especially in the first two rounds.

"Some things just didn't work as they did before, even though I was working the same way," she added.

"I feel like I did really everything I could in pre-season to improve some stuff that I wanted to.

"Then I came here and I wasn't playing natural anymore."