Maria Sharapova struggled to find her rhythm Sunday but advanced to the second round of the China Open td number one and the 12th seed in Beijing, defeated Bulgaria's Tsvetana Pironkova in straight sets, 6-4, 7-6 (7/5), in a duel of 23-year-olds that lasted more than two hours in warm afternoon sun.
The Russian, looking to bounce back after crashing out of the Pan Pacific Open last week in Tokyo in the first round to Japanese veteran Kimiko Date Krumm, used powerful groundstrokes to escape from danger in the first set. But the three-time Grand Slam winner faltered in the second set, trading three breaks of serve with Pironkova before sealing the match with a crosscourt backhand winner to end the tiebreaker.
Stosur, the fourth seed here, started strong but could not hold on, crashing out of the tournament in three sets to 20-year-old Latvian qualifier Anastasija Sevastova, 2-6, 7-6 (7/5), 7-5.
In the third set, the Australian world number seven - who reached the final at the French Open this year - gave her opponent too many second serves to look at and was unable to recover from a crucial service break near the end.
Last year's winner here, 10th seed Svetlana Kuznetsova, also lost in the first round to Italy's Roberta Vinci. In other action, China's ninth-seeded Li Na breezed into the second round, as did a trio of Russians - 13th seed Nadia Petrova, 2005 China Open champion Maria Kirilenko and Alisa Kleybanova. France's Aravane Rezai, the 14th seed, lost to Argentina's Gisela Dulko.
The 6.6-million-dollar China Open is a joint WTA-ATP event, with both tours looking to make inroads in the vast Asian country, which they see as a strategic marketplace. Denmark's Caroline Wozniacki, the top seed in Beijing, could take over the world number one ranking from Serena Williams - who withdrew due to injury this week - by reaching the quarterfinals or better here.
Titleholder Novak Djokovic is the top seed in the men's draw, which begins on Monday. The Serb will face a tough challenge from Britain's Andy Murray, in action for the first time since a disappointing early loss at the US Open.