Jelena Dokic let out a huge yelp of delight after outgunning fifth seed Nadia Petrova 6-4, 7-6 at the Paris Open on Thursday to book a meeting with Kim Clijsters in the last eight.
The Australian, who has fallen so far from her career-high ranking of number four in 2002 that she had to qualify for the first round, looked the better player throughout on the hardcourt against the 2007 winner.
Belgian top seed Clijsters, who has seen main threat Maria Sharapova of Russia withdraw with a virus, only needs to beat Dokic on Friday to depose Denmark's Caroline Wozniacki as world number one but she can expect a tough encounter.
"I feel good, it's a great start to the year for me. I'm getting better and better," Dokic, who surprised last year's runner-up Lucie Safarova in the first round, said courtside.
"I have nothing to lose against Kim. She's number two, almost number one in the world, so I'm just going to go out there and enjoy it."
It was the only mini-shock at the Stade Coubertin, where retired French former world number one Amelie Mauresmo is now tournament director in a bid to boost its profile under the shadow of the more famous French Open and Paris Masters.
Estonian third seed Kaia Kanepi knocked out Sweden's Sofia Arvidsson 6-3, 6-4 with eight-seeded Slovakian Dominika Cibulkova next up in Friday's quarter-finals.
Fourth seed Petra Kvitova outwitted fellow Czech Barbora Zahlavova Strycova 6-4, 6-7, 7-6, seventh seed Yanina Wickmayer of Belgium beat another Czech Klara Zakopalova 6-1, 6-3 and Andrea Petkovic defeated Kristina Kucova of Slovakia 6-4, 6-2.
German number six seed Petkovic will next meet American Bethanie Mattek-Sands, who unveiled another striking black outfit when overwhelming France's Stephanie Cohen-Aloro 7-5, 6-3.