Miami - Roland Garros finalist, Samantha Stosur defeated China's Zheng Jie 6-2, 6-1 on Thursday to reach the third round of the $9 million WTA and ATP Miami Masters Series hardcourt tournament.
The fourth seed, ranked fifth in the world, has played the Miami quarter-finals for the past two editions, losing to the eventual champion on both occasions, Victoria Azarenka in 2009 and Kim Clijsters last year.
Danish top seed Caroline Wozniacki opened with a 6-2, 7-5 victory over American Bethanie Mattek-Sands while Serb sixth seed Jelena Jankovic defeated Romanian Monica Niculescu 6-3, 6-1, in other second-round matches.
Stosur has been getting off to fast starts, having won her opening match at her previous seven events.
"I thought I played quite well," Stosur said. "I don't think I hit the ball out of this world fantastic, but I guess I did what I had to do.
"Against a player like Zheng, you want to be able to do that from start to finish. She always competes hard for every single point. I served really well today, which also helped me get through."
The Australian took just 58 minutes to advance as she never faced a break point but broke her Chinese opponent's serve on six of a dozen chances.
Stosur next plays Lucie Safarova, who beat Swiss veteran Patty Schnyder 6-2, 6-4. Stosur has lost all three of her matches against the 31st-ranked Czech.
"She's a good player who can pretty much beat anyone on her day," Stosur said. "I haven't played a lefty for a little while. That's something to have to adjust to, especially on the return of serves."
The loss was the fifth for Zheng this season, with the Chinese player managing only two wins.
The wrist surgery patient now stands 59th on the WTA list, her lowest since the 2008 Wimbledon.
Zheng was a Miami quarter-finalist in 2006.
Tenth seed Shahar Peer was bundled out in her first match, losing to Spain's Anabel Medina Garrigues 6-2, 6-2.
Slovak Daniela Hantuchova put out American Melanie Oudin 6-1, 6-3 while Czech Klara Zakopalova accounted for Britain's Elena Baltacha 7-6 (7/4), 6-3.
the men were playing in the first round, with seeds all given byes.