With the excep-tion of a couple of shocks, the women's tournament has progressed without serious incident, but there could be fireworks tomorrow when Victoria Azarenka and Sloane Stephens square off for a quarter-final berth.

It was here 12 months ago that the two last met, in a semi-final which is remembered mostly for a medical time-out from Azarenka, at a crucial time, which threw the young American off her game.

Tomorrow they meet two rounds earlier but the intensity is likely to be the same because there is no hiding from the fact that they just don't like each other.

Stephens, who booked her place in the last 16 with a 7-5, 6-4 win over Elina Svitolina of Russia, shares an agent with Azarenka but when asked what her relationship was with the Belarusian, answered: "Non-existent".

Azarenka, who is bidding for her third straight Australian Open title, was equally cool after her 6-1, 6-0 thrashing of Yvonne Meusburger of Austria.

Asked what she had learned from the experience of last year's semi-final, when she was booed by the crowd in Rod Laver Arena, she answered simply: "nothing".

In last year's semi-final, Azarenka led 6-1, 5-3, but then was riddled with nerves when trying to serve it out, and after missing five match points, was broken. The momentum was very much with the American but at that point, Azarenka took a time-out, which was taken off-court and lasted 10 minutes.

The break frazzled Stephens, who was appearing in her first Grand Slam semi-final, and Azarenka duly broke to win.

Azarenka claimed in the courtside interview that she had "almost done the choke of the year" but did not refer to any injury or health problem, only to change her tune later on. It was an incident that left a nasty taste in the mouth and when they meet tomorrow, Stephens is looking for revenge.

"I'm just looking forward to getting back on the court [against her]," the 20-year-old said. "She's won a Grand Slam, she's been in that position a lot of times. It was definitely a learning experience for me.

"Looking back on it I don't think that affected anything too much, but definitely now, if I was in the same position, I know what I have to do. I have to play my game and focus on myself and focus on what I do best."

Stephens has had her ups and downs on and off the court in the past 12 months, cryptically saying at one stage that her biggest wish was that "boys weren't so stupid".

But the American said she had matured a lot, leaving her better able to deal with uncomfortable or unusual situations.

"I'd say I don't get flustered as easily," said Stephens, who recently started working with coach Paul Annacone, the former coach of Pete Sampras and Roger Federer. "It's something I have worked on. I don't get overwhelmed and I'm kind of just learning to focus on myself, because that's the only thing I can control."

Azarenka said she expected a tough challenge from Stephens but claimed that any bad blood between them was in the past.

"We left it all last year here," she said. "I think she improved a lot. She proved that she can handle big stages. She can play against top players. So it's always going to be tough when a player like that knows how to handle themselves. I'm looking forward to it."

Third seed Maria Sharapova had to dig deep before advancing to the last 16, saving a set point in the second set before seeing off Alize Cornet of France 6-1, 7-6.

The Russian was not at her sharpest, having had a long, stressful match in the previous round, played in extreme heat.

"Everyone who played in those conditions is going to feel physically and emotionally tired, and that's the way it goes," the Russian said. "You just have to find a way to get through it. That's what I did. It was quite tough. She had a chance to level the match out and go into a third set, which is something I didn't want to do. I was happy I was able to finish it in two."

Sharapova, who now plays Dominika Cibulkova, said her right shoulder, which needed rest at the end of last year, was not giving her any problems.

"Recovery, for the rest of my career, is going to be extremely important, making sure I do the right amount of work to the right amount of rest that I give it. But it's feeling good," she said.

Former world No 1 Caroline Wozniacki was beaten by rising Spanish star Garbine Muguruza 4-6 7-5 6-3, while another former world No 1, Jelena Jankovic, cruised through to a meeting with Simona Halep of Romania, by overcoming Kurumi Nara from Japan 6-4, 7-5.