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Hsieh Su-Wei continued her outstanding run at the Australian Open, rallying from 3-5 down in the third set to upend Sara Errani 6-4, 2-6, 7-5 and advance to the Round of 16.

Having defeated 2020 US Open quarterfinalist Tsvetana Pironkova and 2019 US Open champion Bianca Andreescu in her opening rounds, Hsieh came into the third round looking to make the second week at a major for just the fourth time in her career. To do so, Hsieh would need to tally her 1st career victory over Errani, who had dominated their three previous matches, handing Hsieh three bagel sets over that span.

With both women possessing superior court craft and tennis IQ, Hsieh and Errani quickly settled in for a physical game of chess-like tennis. Over the course of 2 hours and 44 minutes, Hsieh and Errani combined for 87 winners. After Hsieh edged the opening set 6-4, Errani quickly struck back. 

The Italian was playing her first third round at a Slam since 2015, and after finding herself too reactive to Hsieh's play in the first set, Errani stepped up her aggression in the second. Errani cleaned up her game to go from hitting 9 winners to 17 unforced errors in the first set, to 17 winners to just 6 unforced errors in the second set. 

Errani and Hsieh traded breaks through the first five games of the final set before Errani gutted out a hold to earn some daylight at 4-2. Hsieh showed no signs of panic. The Chinese Taipei star continued to protect her serve to keep the scoreboard pressure on Errani and Hsieh's efforts finally paid off as Errani served for the match at 5-4. 

Errani would not win another game. Hsieh broke Errani with back-to-back 10-shot and 14-shot rallies, and then won 8 of the last 10 points of the match to seal the comeback win. 

Hsieh will face 2019 Roland Garros finalist Marketa Vondrousova in the Round of 16. The Czech lefty defeated Sorana Cirstea 6-2, 6-4 to advance to her first Round of 16 in Melbourne. Seeded No.19, Vondrousova has lost just one set in the first week and says she's slowly figuring out how to play her game on the quick courts at Melbourne Park.

"So my first match was tough," Vondrousova told reporters after the win. "I was down like 2-6, 1-3 and that was kind of crazy. But I don't know, I managed to get the win and for me I'm just very happy to be on court right now and I feel like I'm playing good tennis. Also I found my game. And I feel like it can be better to serve also. 

"But I don't know, I managed to win in like two sets like the last two singles, so it's nice for me and I'm just very happy to be in the second week."

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Muguruza, Osaka cruise into Week 2 to set up tantalizing clash

Former World No.1 Garbiñe Muguruza capped off an efficient, business-like Week 1 at the Australian Open with a 6-1, 6-1 win over Zarina Diyas in the third round. A finalist last year, Muguruza needed just 56 minutes to book her spot in the Round of 16, where she will face No.3 seed Naomi Osaka, who defeated No.27 seed Ons Jabeur 6-3, 6-2 in one hour and 18 minutes.

On Friday afternoon, No.14 seed Muguruza continued to ride her wave of momentum at Melbourne Park, where she advanced to the Yarra Valley Classic last week before losing to World No.1 Ashleigh Barty. Muguruza came into her match against Diyas having lost no more than four games in her previous two matches and averaging just seven unforced errors per set. The Spaniard continued that trend against Diyas, who pushed her to the limit at the 2020 Shenzhen Open. Muguruza won that match, 4-6, 6-2, 4-6.  

"Very happy also again with my performance today," Muguruza said. "I feel like the last match, it was a year ago in China. It was very tough battle. I felt like I was more prepared this time after many matches and after playing well.

"I feel like I took control early of the match and kept on going. So happy that this time was not a three-set match. Just happy with, of course, being in the second week of a Grand Slam. Just shows that my game is there."

Rivalling Muguruza's meagre 10 dropped games for first-week dominance is fellow former World No.1 Osaka, who has made her way into the fourth round for the loss of only 13 games in three matches - all against former Grand Slam quarterfinalists. In a first professional encounter with Jabeur, the 2019 champion once again showed her clutch qualities: Osaka found herself pushed to the limit off the bat, but survived 14 deuces and five break points against her in her first three service games alone.

Afterwards, the Japanese player said that the key to dealing with Jabeur's unpredictable shotmaking was to focus on the basics. "My biggest thing I wanted to focus on today was my serve and my return, because those are the things that I can control," she told the press. "I didn't know what would happen during the point, but I do know that I can control if I can get the return back and I can control how I start off my serves. So I was just basing my entire plan around that."

It's a plan that enabled Osaka to roll following the challenging start, striking 26 winners to 28 unforced errors in total and breaking the Tunisian four times to set up another tantalizing first-time matchup with Muguruza.

"I've practiced with her once," Osaka recalled. "But it was on grass, and I was younger. It was maybe a couple years ago. But I just remember being really impressed by her. I've watched her win Wimbledon and the French Open when I was younger, and I've always wanted to have the chance to play her. So for me, this is really exciting."