The top seed Caroline Wozniacki faces a monumental test at the Australian Tennis Open this afternoon when she squares off against defending champion Kim Clijsters in the quarter-finals.
The Dane is yet to win a grand slam title, while Clijsters has four, and the world number one is in danger of losing her ranking if she's knocked out by the Belgian star.
Nonetheless Wozniacki is slight favourite to win the match and she says Clijsters will need to be on top of her game in Melbourne.
Wozniacki's clash with Clijsters headlines the afternoon matches alongside the first men's quarter-final between third seed Roger Federer and Argentine powerhouse Juan Martin del Potro.
