World number one Maria Sharapova battled her way into the fourth round of the French Open with a 7-6 6-0 victory over Italian Karin Knapp on Saturday.

The Russian top seed needed an hour and 58 minutes to see off the 32nd seed and set up a meeting with compatriot Dinara Safina, a 6-2 7-5 winner over China’s Zheng Jie.

Sharapova, a semi-finalist at Roland Garros last year, won the opening set tiebreak 7-4 after a tight 81 minutes with a crosscourt backhand winner.

The contest turned her way when she broke in the 13-minute second game of the second set and Knapp, who had only won two matches on clay this season before arriving in Paris, bowed out after netting a smash.