OSAKA, Japan (AP) -- Top-seeded Samantha Stosur of Australia advanced to the second round of the Japan Open by beating Erika Sema of Japan 6-4, 6-2 on Monday.
Stosur, who won the tournament in Osaka in 2009, had five aces and converted 5 of 6 break points.
The ninth-ranked Stosur reached the semifinals of the Pan Pacific Open in Tokyo earlier this month and is seeking her first title of the year.
Chang Kai-chen of Taiwan defeated third-seeded Christina McHale of the United States 6-3, 7-6 (5), and American Jamie Hampton beat Ayumi Morita of Japan 6-3, 6-2.
Pauline Parmentier of France, Casey Dellacqua of Australia, Heather Watson of Britain and Misaki Doi of Japan also advanced to the second round.