Shenzhen, China (SportsNetwork.com) - Kazakhstan's Zarina Diyas was a first- round winner Sunday at the season-opening Shenzhen Open tennis tournament.

The fourth-seeded Diyas posted a 6-3, 6-1 victory over Croatian Donna Vekic on the hardcourts at Shenzhen Longgang Tennis Centre.

Fifth-seeded Czech Klara Koukalova fell 6-3, 4-6, 7-6 (7-5) to Slovakian Anna Schmiedlova, while eighth-seeded Timea Bacsinszky outlasted Stefanie Voegele 6-1, 4-6, 6-4 in an all-Swiss affair.

Russian wild card Natalia Vikhlyantseva, Hungarian Timea Babos and China's Zheng Saisai also won first-round matches.

Li Na beat Peng Shuai in last year's all-Chinese finale.

Shenzhen serves as a tune-up for the Australian Open, which will begin January 19 in Melbourne.