Sania Mirza sailed into the Japan Open quarterfinals after notching up a straight-set win over Ukraine's Viktoriya Kutuzova.

Indian tennis ace Sania defeated Kutuzova 6-4 6-3 in one hour and 23 minutes to set up a tough quarterfinal against second-seeded Frenchwoman Marion Bartoli.

Both Sania and Viktoriya served badly in the opening set, committing five double faults each on Wednesday. But Sania managed to convert a crucial break point to go 1-0 up.

The Indian was more in control in the second set and she cut back on her service errors, saving three of the four break points she faced.

Viktoriya, however, continued to serve poorly and was broken thrice by the Indian, who was also helped by the three double faults the Ukrainian committed.

Sania goes into the match against world number 12 Bartoli with a 1-0 head-to-head record as the Hyderabadi had beaten her in the 2005 US Open.