World number ones Serena Williams and Roger Federer have knocked out the last remaining home players to reach the quarter-finals of the Australian Open tennis championship in Melbourne.
Federer, his confidence and form growing with each match, extended his winning streak against Lleyton Hewitt to 15 with a straight sets victory in less than two hours, while Williams showed no mercy against Samantha Stosur, winning 6-4 6-2 in a little over an hour.
Williams is the only woman in the top five left in a draw that has produced an unexpected lineup of quarter-finalists, including two from China - Zheng Jie and Li Na.
6th seed Venus Williams and 7th seed Victoria Azarenka also won through to the last 8.
In the men's draw 3rd seed Novak Djokovic remains untested after scoring a straight sets win over Pole Lukasz Kubot, while there were wins for 6th seed Nikolay Davydenko and 10th seed Jo-Wilfried Tsonga.
