Reigning champion Victoria Azarenka wasted little energy in making the Australian Open quarter-finals Monday as Svetlana Kuznetsova roared back to form with an upset win over Caroline Wozniacki.
The top seed took less than an hour to dispose of Elena Vesnina 6-1, 6-1 to set up a last eight meeting with the veteran Kuznetsova, a two-time Grand Slam winner who spent two months on crutches last year.
The experienced Russian needed a tense 2hrs 28mins to oust 10th seed and former world number one Wozniacki 6-2, 2-6, 7-5 on Rod Laver Arena.
Exciting American teenager Sloane Stephens also stayed alive, beating Serb Bojana Jovanovski in a tough 6-1, 3-6, 7-5 battle to make her first Grand Slam quarter-final.
She will face either Serena Williams or Maria Kirilenko, who play later.
"I can see Sveta came back much fresher, much stronger," Azarenka said of her clash with Kuznetsova.
"She knows how to handle big stages, big tournaments. She's a Grand Slam champion. It's definitely an exciting match for me to be in."
The Belarusian world number one was in red-hot form off the baseline against Russia's unseeded Vesnina, but seven double-faults blotted her performance.
Vesnina, who won the Hobart International warm-up tournament, has not beaten a world number one before and never looked like improving her record.
Kuznetsova has dropped down the rankings to be 75 in the world, but she showed her quality against Wozniacki, who has been struggling for form.
It was a courageous win by the Russian after an injury to her right knee forced her to skip a big chunk of 2012.
The injury meant she missed all post-Wimbledon events including the US Open, which ended her streak of 40 straight Grand Slam appearances dating back to 2002 at Flushing Meadow.
But Kuznetsova, who won the 2004 US Open and 2009 French Open, said she was feeling fresh again and delighted to be in her first Grand Slam quarter-final for two years.
"I think the tournament in Sydney helped me a lot because I had a few matches," the 27-year-old said of the lead-up event to the opening Grand Slam of the season.
"I have been working hard, but still I didn't have much time to do what I like to do with my fitness, condition and everything else."
"So, it's amazing," she added, of making the last eight.
The defeat was another disappointment for Wozniacki, whose preparations for Melbourne were hurt by going out early at both the Brisbane and Sydney International tournaments.
"Obviously I would have loved to have won today, but it didn't happen," said the Dane, whose golf-star boyfriend Rory McIlroy also had a poor start to his season, missing the cut in Abu Dhabi on Friday.
"There is still a long year in front of me. There are still a few things I can work on and, you know, it can be better."
On Hisense Arena, Stephens was made to dig deep for her first appearance in a last eight at a major.
The 19-year-old, whose poise and power has seen her compared to a young Williams, displayed all her attributes.
Stephens steamrolled through the first set before the 56th-ranked Jovanovski, 21, woke up and gave her a fright, forcing the match into a tense three-set tussle.
"I don't know what happened after the first set but she played great tennis," said Stephens, adding that she hoped to play Williams next.
"I haven't beaten Serena and I hope I'll give you all a good show."