Maria Sharapova brushed past Tamarine Tanasugarn to reach the third round of the Pan Pacific Open.
The former US Open champion overcame her Thai oponent 6-2 7-5 in one hour and 31 minutes in Tokyo.
It was a welcome return to form for the world number two after her third-round exit at the US Open earlier this month.
Having won the first set with little resistance, the Russian was pushed harder in the second set before finally claiming victory.
Tanasugarn trailed 3-0 in the second set before springing to life, breaking her Russian opponent in the fourth game, and winning five of the next seven games to make it 5-5.
But Sharapova's greater experience shone through as she held her nerve and clinched victory with an ace.
In other second round action, seventh seed Marion Bartoli of France defeated Ayumi Morita of Japan 6-3 0-6 6-3.
Serbia's Ana Ivanovic, the 12th seed, had no problems as she overcame qualifier Anastasia Rodionova of Australia 6-4 6-0.
The Tokyo crowd were denied a home victory as veteran Kimiko Date-Krumm lost 1-6 6-3 6-3 to Mandy Minella of Luxembourg.