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Current World No.1 Ashleigh Barty and former World No.1 Karolina Pliskova both overcame tricky challenges inside Rod Laver Arena on Thursday at the Australian Open, moving through to the third round in straight sets.

Up first, Pliskova avenged a third-round defeat at the Yarra Valley Classic to 2019 semifinalist Danielle Collins from just eight days ago 

"It was tough because we played last week. The match was very close. At least I knew how she's playing little bit," Pliskova said after the match.

"I just played better in some moments, which I didn't last week. Then she was not playing that well as she did last week. I knew if I at least maintain little bit, just play at least similar as I was playing last week, I knew it's going to be difficult for her to repeat what she played last week. I think she really played great.

"That was about it today. It was more about like staying positive, staying in there."

Twice a break up in the first set, Pliskova didn't wrap up a one-set lead until her third opportunity, as Collins saved a set point in the 10th game to get back on serve.

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Having excelled in clutch moments last week to defeat the Czech in a pair of tiebreaks, the American was unable to replicate that form inside Laver: from 2-0 down in the second set, Pliskova rolled through the last six games.

Up next for Pliskova is another Czech player, No.25 seed Karolina Muchova, who eased past German veteran Mona Barthel, 6-4, 6-1.

"Today I think I played a bit of a better level than I did in the first match. I felt better and I stayed in the rallies. The first set was a bit shaky, but then in the second, I just went all the way and I'm happy with that," Muchova said. 

"I felt like I could play rallies with her. I went for my shots, finished at the net and had great returns, so I'm just happy with today's performance."

The pair split two meetings in 2019, with Pliskova winning with ease in the first round at Melbourne Park before Muchova pulled off a stunning upset at Wimbledon in a breakthrough quarterfinal run.

The two also practiced together in the two-week quarantine period as a part of the same cohort. 

Karolina... on Karolina

"We know each other so much. Even if we would've not practiced those two weeks in quarantine, we practice a lot in Czech. We're actually quite good friends. She's a dangerous player. She can play well. She has a different style. It's going to be very tricky. I think it's going to be at least like good atmosphere, there is not really the tension that we hate each other. I think it can be good match."

- Karolina Pliskova on Karolina Muchova

"We know each other pretty well and we're good friends. I just expect a tough match. She's a very good player. Maybe it can be an advantage that I know what to expect, I think she does, too. I don't expect anything else but a tough battle... but I'm excited about it."

- Karolina Muchova on Karolina Pliskova

 

All-Aussie affair goes to Barty 

Barty looked on court to cruise through to the last 32 as she built a 6-1, 5-2 lead against compatriot Gavrilova in under an hour, but the former Top 20 player didn't allow the top seed to have it all her own way.

In the end, Barty needed to save two set points — after losing four straight games to fall behind 6-5 — in a second-set tiebreak before wrapping up a 6-1, 7-6(7) win.

"I think I was doing all the right things up until that point, then I feel like I a little bit just lost my way tactically, more with just having the right intent and going about it the right way," Barty told reporters after the match.

"I think more than anything I probably felt like the set was turning into a bit of a prickly pear, really... but in the end, I was happy to be able to bring it back around in the tiebreak when I needed to and win some big points."

Barty has now beaten Gavrilova in four of their five career meetings, though the two had not played in nearly two years. 

"It's so nice to see her back. She's had a bit of a tricky run with injury over the past 18 months or so, so it's just so nice to see her back here competing," Barty told former doubles partner Casey Dellacqua in her on-court interview.

"When you play another Aussie or you play a compatriot, the rankings go out the window, experience goes out the window. Typically, you know each other really well, so it was always going to be a tricky match no matter what."

Up next for Barty is a match against Gippsland Trophy semifinalist No.29 seed Ekaterina Alexandrova of Russia, who beat Czech Barbora Krejcikova, 6-3, 7-6(4), to reach the third round of the Australian Open for the second year in a row.

"I've never hit with her. That's a new one for me. I think that's the time for Tyz [coach Craig Tyzzer] and I to sit down and do our homework. Tyz is extremely diligent with all the work that he does. He's the best in the business. I'm very fortunate to have him in my corner.

"We'll kind of sit down and work from there, try and work out a game plan as best that we can. Then it's about I suppose the challenge of now having someone that I haven't played against that I can go out there and test myself against.

"She's obviously playing some very good tennis, had a great week last week as well. Certainly has got her foot firmly set in the season, is going ahead well.

"There are no easy matches in any tour event, any Slam, anything. I think every time you walk on the court, you have to try and be able to bring your best tennis to be able to compete with everyone."