Serena Williams has reached the quarter-final of a grand slam for just the second time in her last five appearances at a major, setting up a showdown with last year's Australian Open runner up, Dominika Cibulkova.
The American, who was bundled out of last year's Australian Open by Ana Ivanovic in the corresponding round, overcame a horror first set to topple Spain's Garbine Muguruza 2-6, 6-3, 6-2 on Rod Laver Arena.
The world No.1 failed to reach the quarter finals at the Australian Open, French Open and Wimbledon in 2014, but did manage to finish the year off on a high with a championship win in front of her home fans at the US Open.
Williams, who had to battle through a strong cough during her match against Muguruza, said her opponent pushed her into producing the best performance of her tournament to date.
"She made me play a lot better," Williams said.
"I had to play the best match of the tournament or else I was going to be out. I think she was just hitting winners like left and right. Every shot I hit, she basically hit a winner on. So I had to change my approach. I was hitting a little bit too much to her."
Fellow American Madison Keys also progressed through to the quarter finals with a straight-sets win against countrywoman Madison Brengle.
Williams will meet Slovakian Cibulkova, who ended the resurgent run of Belarusian crowd favourite Victoria Azarenka in the curtain raiser on centre court.
While Azarenka was disappointed not to add to her two Australian Open titles, the unseeded 25-year-old admitted there were plenty of positives to take out of the tournament after missing a lot of 2014 through injury and personal reasons.
"Definitely, compared to last year, it's a big difference but, just overall, I think my attitude and my approach to matches, to tournaments, has changed," Azarenka said.
"That's more satisfying for me. I feel that I'm very honest with myself on my effort and I'm working really hard. I'm just trying to do my best, so there are things I can be pleased with. As I said, I want to be realistic and I want to do better.
"I don't want to stop here and be, OK, this was a good match. I want to strive for much better. I'm just going to work hard, try to analyse this match, this tournament, and keep working. I think that the direction where I'm heading is the right way ... I just need to go there step by step."
Cibulkova, who is coming off a first-round exit in Brisbane and a second-round loss in Sydney, has developed a love affair with Melbourne.
She knocked over Maria Sharapova, Agnieszka Radwanska and Simona Halep on her way to losing last year's final against Li Na.
The 25-year-old insists she isn't feeling any extra pressure given her giant-killing run at Melbourne Park in her last two campaigns.
"I don't know if – I don't see myself like I have to be in the final," Cibulkova said.
"It's never easy. Even the big names, the big players, it's not easy to defend something like this. So I don't think like this. It's a new year. It's a new start. I'm starting the year pretty well again. So this is how I see it."
Cibulkova has an 0-4 record against Williams, but the American refuses to write off the Slovakian pocket rocket.
"Well, she is a really good player. I mean, to be her size, she hits so hard and she plays so well," Williams said.
"She's just such a power, compact, great player. I just have to stay focused and not underestimate her. She actually almost beat me before. I want to make sure I come ready and prepared."
