Former doubles winners Yan Zi/Zheng Jie romped past Czech pair Nicole Vaidisova/Barbora Zahlavova Strycova 6-4, 6-1 to make last eight at the Australian Open in Melbourne yesterday.

Their compatriot Sun Tiantian booked a third round berth in the mixed doubles together with Serbian Nenad Zimonjic.

The Chinese legion suffered huge blow one day before when Peng Shuai/ Sun were ousted from the doubles second round and Li Na stopped in the singles third round on Sunday.

"Vaidisova is a good singles player with good serves. I think we won because we did thorough preparation before the match," said Zheng, who won the Sydney title with Yan.

"Yesterday my teammates lost their matches but I don't feel any pressure just because we are the only pair left. All I and Yan think about is how to dig deeper into the draw," she added.

Yan and Zhang next will face either American sisters Venus and Serena Williams or Maret Ani, Estonia/ Meilen Tu, United States.

"Our next opponents might be the Williams sisters. It is a good opportunity for us during our run-up to the Beijing Olympic Games," she said.

Fifth seed Sun and Zimonjic enjoyed an easy match against Liezel Huber of the United States and British Jamie Murray, winning 6-2, 6-4.

Sun and Zimonjic made only three unforced errors against their opponents' 11 in the 62-minute match.