Venus Williams set up a third round showdown with in-form fellow former world No.1 Maria Sharapova by outclassing Frenchwoman Alize Cornet at the Australian Open on Wednesday night.
Sharapova is emerging as sister Serena Williams' biggest title threat after the Russian second seed annihilated Misaki Doi 6-0 6-0.
But doubt lingers over the fitness of Serena Williams, after the tournament favourite rolled her ankle during her first-round win over Romanian Edina Gallovits-Hall.
The American's second-round appearance remains under a cloud after she told tournament officials late Wednesday that she wanted to train indoors away from media and the public.
Williams says she will know whether it is a serious problem within 24 hours.
The fourth seed Agnieszka Radwanska, who won the ASB Classic in Auckland, is also into the last 32.
Meanwhile Australia's Samantha Stosur agreed she had 'choked' to lose her second round match against China's Zheng Jie.
She blew a 5-2 lead in the final set to continue her dismal run in her home grand slam, losing 6-4 1-6 7-5.
The US Open champion in 2011 was serving for the match before her nerves seemed to get the better of her, allowing Zheng to claw her way back and reel off five successive games to clinch a place in the third round.
