Top seed Ash Barty was tested on Wednesday, with the top seed forced to save six break points before securing a 6-1, 6-4 win over Slovene Polona Hercog in the Australian Open second round.

Barty battled the wind in her 68-minute victory four days after winning the title in Adelaide.

Ash Barty won through to the third round.  Photo Anne Parker International Sports Fotos Ltd/Alamy Live News

“The wind was a massive factor today, it changed end to end dramatically,” the WTA No. 1 said. “It was important for me to get a good start, and I was able to do that.

“Every time you’re able to win a match, you have another opportunity to try and be that little bit better, to try to be that little bit more sharp and clean.

“I felt like I started a lot better today, and then the second set, I  was able to get out of some sticky service games towards the end of the set there.”

The career of Caroline Wozniacki will live on for at least another round after a 7-5, 7-5 win over weekend Adelaide finalist Dayana Yastremska.

Caroline Wozniacki press conference after winning second round match. Photo: Roger Parker International Sports Fotos Ltd

The Ukrainian challenger got away to a double break in the opening set over the 2018 Melbourne winner but was hauled back as Woz claimed the opener and fought through for victory in two hours.

The Dane who will retire when her Melbourne run is over thrived on fan enthusiasm.

“The crowd is really supporting me out there and standing behind me and it’s amazing. This is a tournament where I’ve always had crowd support, so it just feels even more special because it’s even more now.

“I feel just lucky to be out there and still playing on a high level.”

Defending champion Naomi Osaka buried her exasperation with the cat-and-mouse game style of a  tricky Chinese opponent to post a 6-2, 6-4 defeat of Zheng Saisai in 80 minutes.

“I definitely got very frustrated in the second set,” the Japanese winner said. “It’s something that I knew would happen, but I didn’t know the scale of what she would do to

“I need to focus on (the fact) that I’m going to have really tough matches and I have to find a way to get around it and just be consistently level-headed.

“She was slicing and dicing and getting everything, that’s basically what happened.”

Osaka next plays US 15-year-old Coco Gauff, who broke new personal ground here with a third round spot courtesy of a 4-6, 6-3, 7-5 defeat of Sorona Cirstea after coming back from 3-0 down in the final set.

That match will be a repeat of the third-round US Open contest of last year, when Osaka defeated the youngster and then comforted Gauff as she wept in defeat on court.

“This is amazing,” Gauff said after her win. “I didn’t think I would get so much support in Australia.

Serena Williams catches her breath as she beats Tamara Zidansek in a second round match. Photo Roger Parker International Sports Fotos Ltd

“It was very emotional, I don’t know why they support me, but I guess they kind of like me.

“This time I’ll be less nervous and confident against Naomi. It was my first time on Ashe stadium (US Open). “And I know her strokes now.”

2019 runner-up Petra Kvitova eased into the third round with a 7-5, 7-5 defeat of Spain’s Paula Badosa  and will next face a player riding a hot streak.

Russian Ekaterina Alexandrova has won her last dozen matches, claiming a December Challenger title in Limoges and starting this season with the Shenzhen trophy.

“The wind was hitting side to side and you never know from where it’s coming,” the double Wimbledon winner  who salvaged three set points, said.

” Today was really about the nerves, about the wind, about the opponent. I really wasn’t playing probably my game,” Kvitova said.

“I was struggling with the serve a little bit but I managed to win it. This match is important to have, for sure.

“It’s the first one I really played well. Today was up and down.”

Slovenia’s Polona Hercog. Photo Anne Parker International Sports Fotos Ltd/Alamy Live News

Spain’s Carla Suarez Navarro, is seeing out what will be her last Australian event in style, knocking out 11th seed Aryna Sabalenka 7-6(6), 7-6(6), with the Belarussian weighed down by nearly 60 unforced errors in windy conditions.

Suarez Navarro, a three-time quarter-finalist here, is due to retire at the end of the season.

German Julia Goeges beat another seeded victims with her defeat of No. 13 Petra Martic 4-6, 6-3, 7-5 to move into the third round.

Ninth seed Serena Williams struggled in the second set to advance past fired up Slovene Tamara Zidansek, with the American ninth seed producing a 6-2, 6-3 survival win thanks to a break in the final game.

Serena Williams struggled to beat Tamara Zidansek.  Photo Roger Parker International Sports Fotos Ltd

“It was a good match for me: Williams who failed to convert on seven break points before finally nailing her eighth. “She’s a fighter.

“I as frustrated after making so many errors in a row. I had to battle through my own internal problems.

“I knew I had to play better, I couldn’t keep making unforced errors I had to step up or it would have been a really long evening.”