The Russian tennis superstar Maria Sharapova is through to the ASB Classic quarter-finals after a straight sets win over Renata Voracova,
The Czech led 3-1 in the first set but Sharapova won the next five games,
The second set was locked at 3-all when Voracova won two games and looked to have a chance of taking the match to a third only to lose the next four games to the tournament's big draw card.
In the quarters Sharapova will play the Hungarian Greta Arn, who ousted the eighth seed Sofia Arviddson of Sweden in three sets,.
Arviddson, who's Maria Erakovic's doubles partner, is the fourth seed elimated today after Svetlana Kuznetsova, Elena Vesnina and Carla Suarez Navarro.
