Maria Sharapova warms up in Hong Kong

Maria Sharapova struggled to a 7-5, 6-3 win over Yan Zi of China in the quarter-finals of the Champions Challenge in Hong Kong on Thursday.

Maria led 5-2 at one stage but was pegged back to 5-5 before breaking her opponent's serve and holding her own to clinch the first set. The Russian came out firing in the second and established a 5-1 advantage which proved too big a gap for Yan to make up.

She wouldn't be drawn on how she rated her chances in the Australia Open later this month following the surprise withdrawal of world number one Justine Henin-Hardenne from the first Grand Slam of the year. "It doesn't matter who you play you just have to concentrate on your own game," she said. Eight of the world's top women's tennis players are in Hong Kong, including number five Kim Clijsters who won her first-round match on Wednesday. The final will be played on Saturday.