Third-seeded Samantha Stosur of Australia defeated Johanna Larsson of Sweden 6-4, 6-2 on Monday to advance to the second round of the Japan Women's Open.
The 29-year-old Stosur didn't face a break point on her serve and converted three of nine break points in the match at Ustubo Tennis Park.
Stosur has had previous success in the Osaka tournament. She won here in 2009, was runner-up in 2011 and a semifinalist in 2012, compiling a 15-3 record in Osaka.
In other first-round matches, seventh-seeded Monica Puig of Puerto Rico beat defending champion Heather Watson of Britain 6-4, 6-4, and fifth-seeded Eugenie Bouchard of Canada ousted Varvara Lepchenko of the United States 6-3, 6-0.
Top-seeded Jelena Jankovic pulled out, citing a left-hip injury. The Serbian player received medical treatment in the second set of her 6-2, 6-2 loss to Serena Williams in Sunday's final of the China Open in Beijing.
