MELBOURNE, Australia - No.7 seed Petra Kvitova avoided a major upset on Sunday, coming back from a set down against an inspired Maria Sakkari to book her spot into the Australian Open quarterfinals. 

Kvitova had yet to drop a set in Melbourne heading into the fourth-round clash, and with just 14 games lost along the way was one of the tournament’s most in-form players.

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Bouncing back strongly after losing a tightly-contested opening set, Kvitova fired 33 winners and broke the Greek player eight times en route to a 6-7(4), 6-3, 6-2 victory. 

“I think, you know, from the beginning it was a lot of nerves out there,” Kvitova said in her post-match press conference. “I didn't feel the best. I was just, you know, too tight and everything was flying somewhere...

“In the end of the day, it was about fighting spirit in a way. Even I didn't play the best, Maria played really great tennis, and it was nice to share court with her, for sure…  I'm so happy that in the end I felt my game again.”

2020 Australian Open press conference: Kvitova ‘a lot of nerves out there’

Full of confidence and in the midst of a breakthrough run in Melbourne, Sakkari made a strong start against Kvitova on Rod Laver Arena. The Greek player lead their head-to-head record 2-1 going into the match, all three of their matches taking place last year. Sakkari had claimed the win in their most previous encounter in Cincinnati in a two-hour, three-set epic. 

“I played her in Miami last year,” Kvitova recalled. “I played a good game, but since then I think that she's really playing better and better. I lost to her in Cincinnati last year, and I think that she really put a lot of work to her game.

“I think that she’s really  very talented, she has a great touch, as we saw today, as well. She has a mix of the shots.

“She has everything for the good game and really she's playing much better.”

Sakkari broke serve in the first game, starting the match with a 2-0 lead. The Greek stayed solid, covering the court with speed and matching Kvitova’s power. Kvitova kept the pressure on, smacking return winners, but found herself unable to create break chances on her opponent’s serve for much of the first set. 

With Sakkari serving for the set at 5-4, Kvitova finally earned her first break to level the score, 5-5. They traded breaks again - Sakkari once again serving for the set at 6-5 - to go into a tiebreaker. But with Kvitova leading 2-0 in the decider, Sakkari found a second wind to surge ahead and win the opening set, 7-6(4).

Dropping her first set of the tournament seemed to jolt Kvitova to life in the second set, breaking early to lead 1-0. Every game save one of the tightly-contested set went to a break point, with Kvitova and Sakkari trading breaks twice to stay even at 3-3. But that’s when the Czech found another level, reeling off the last three games in a row to level the match at a set apiece.

Sakkari was unable to maintain the level that she’d reached in the first half of the match, and Kvitova dictated the rallies with her powerful lefty forehand. She broke early to open up a 3-0 lead, and then closed out the set with another break - her eighth of the match - to close out the battle after two hours and 12 minutes. 

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Into the quarterfinals in Melbourne for the fourth time, Kvitova awaits the winner between World No.1 Ashleigh Barty and No.19 seed Alison Riske in the next round.