'Can't believe it': Tennis world stunned by 'insane' Naomi Osaka drama

Naomi Osaka has staged an extraordinary comeback to keep her Australian Open hopes alive, storming home to knock Garbine Muguruza out in the fourth round.

Ash Barty now has one less grand slam champion to contend with after Osaka beat Muguruza 4-6, 6-4, 7-5 on Sunday.

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The US Open champion and former Australian Open champion, Osaka trailed 3-5 in the third set and saved two match points before reeling off four-straight games to advance to the quarter-finals.

Osaka was staring down the barrel while serving at 4-5, 15-40 in the deciding set, but came up with a clutch ace and booming forehand winner to save the pair of match points.

"She was gone," one commentator said in disbelief on Channel Nine.

After dropping her serve at 2-2 in the third set, Osaka threw her racquet in disgust and looked destined for the exit door.

But the 2019 Australian Open champion showed why many are predicting her to re-produce her title run at Melbourne Park.

Osaka finished with 40 clean winners and 36 unforced errors after needing to redline it to keep Muguruza at bay.

The Spanish star's only defeat in eight matches this summer came against world No.1 Ash Barty in the final of the Yarra Valley Classic lead-up event.

Osaka knew she was in for a torrid day out in her first career meeting with Muguruza.

"I feel like today I didn't really know what to expect because I'd never played her before," Osaka said.

"I just knew it was going to be tough. I was a bit intimidated because I knew she was playing really well coming into this match.

"In the stressful points, I feel like I just had to go within myself and I know that I probably hit a lot of unforced errors but it was something I needed to do.

"I couldn't really give her any short balls because she would finish it."

Fans were equally stunned by Osaka's comeback and Muguruza's collapse.

Hsieh makes tennis history at Australian Open

Osaka will now play Hsieh Su-Wei in the quarter-finals after the Taiwanese player scored a huge boilover win against 19th seed Marketa Vondrousova.

The 35-year-old eclipsed her previous best grand slam performance with a 6-4 6-2 victory over the Czech on Sunday.

It means Hseih will the oldest female player in tennis history to play in their first grand slam quarter-final.

Hsieh got an early break in the opening set and never looked troubled over the 19th seed, a player she also toppled in an Abu Dhabi warm-up event in January.

"It was a little bit strange with the crowd, but a great win," she said.

Hsieh, by far the least decorated player left in her side of the draw, had already shown her mettle by beating 2019 US Open champion Bianca Andreescu en route to meeting Vondrousova.

She made her grand slam debut in 2005 but had never gone beyond the fourth round before in 37 previous attempts.

with agencies

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