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By Nick Mulvenney
MELBOURNE, Feb 14 (Reuters) - Naomi Osaka saved two match points as she battled back from the brink to reach the quarter-finals of the Australian Open with a 4-6 6-4 7-5 victory over in-form Garbine Muguruza on Sunday.
The Japanese third seed was chasing the match from the start on Rod Laver Arena and looked defeat square in the face in the third set when the Spanish 14th seed had two opportunities to win the match with a break of serve.
Osaka saved both match points -- the first with an ace -- to turn the tide in the contest decisively and Muguruza exited the tournament a couple of games later after failing to win a point in her final service.
Fans remained absent from Melbourne Park for a second day because of the state of Victoria's coronavirus lockdown and Osaka's victory was greeted with taped applause piped into the stadium.
"I'm tired right now, that was tough," said Osaka, who mixed 40 winners with 36 unforced errors over the contest.
"Today I feel like I was intimidated, she is playing well. I had to go within myself, I couldn't play short balls to her because she'd put them away."
Next up for Osaka is an all-Asian quarter-final against unorthodox 35-year-old Hsieh Su-wei of Taiwan, who will be playing in the last eight of a Grand Slam for the first time.
"I'm not looking forward to it, every time we have played it's three sets," Osaka added. "It's fun when I'm not really angry. When I play her I just have to expect everything."
Although Osaka had never played Muguruza before, she had perhaps a better idea of what to expect from the former French Open and Wimbledon champion.
Muguruza, a finalist here last year, had conceded only 10 games in reaching the fourth round and continued that rich vein of form into Sunday's match.
Serving solidly and pouncing on anything short of perfect that flew off Osaka's racket, she grabbed what looked to be a crucial break of serve for 5-3 in the third set by steering a lovely backhand winner down the line.
Muguruza rued her missed opportunity but said she was happy overall with the start to her season.
"It's never a good feeling losing a match that you feel you could have changed in one second," the 27-year-old said.
"But I left the court with a good feeling, very good feeling about this tournament in general."
(Editing by Peter Rutherford)