SYDNEY - Francesca Schiavone upset US Open champion Samantha Stosur's preparations for next week's Australian Open with a straight sets opening round win at the Sydney International on Monday.The Italian matched home favourite Stosur's power with aggression to secure a 6-2, 6-4 win in 90 minutes in the feature match on Ken Rosewall Arena. The loss followed Stosur's second-round exit from the Brisbane International last week and has left the world number six short of match practice heading into the season's first grand slam starting in Melbourne on Monday.Schiavone, ranked 11, has been a tricky opponent for Stosur, beating her in the 2010 French Open final and in last year's Fed Cup tie in Australia. "I think I was really aggressive, and she couldn't play her game at the best," said Schiavone, who next plays Daniela Hantuchova."You have to play at a top level, and I think it's not easy for her to play here in Australia. I think to play at home, when you love something, is tough to catch it. For the Australian Open it will be different. She has big power and big shoulders to do it."Stosur, who mastered Serena Williams in last year's US Open final, said she failed to cope with the centre court crowd's expectations. "I think today I certainly didn't handle that side of things at all well," Stosur said. "I think playing in Australia, I want to play the best I can play and do it all here this month right here right now. Then when it doesn't happen, it's obviously disappointing. It probably makes it more disappointing here than anywhere else." Defending champion Li Na, third seed Victoria Azarenka and eighth seed Marion Bartoli all progressed to the last 16. China's Li needed just an hour to sweep past Russia's Ekaterina Makarova 6-0, 6-3 after reeling off the first nine games of the match. Li, the first Asian player to win a grand slam, beat Kim Clijsters in last year's Sydney final before losing to the Belgian two weeks later in the Australian Open final. "Last year is over," the world number five said. "I don't have to think about what I did already last year. I mean, everyone has to look forward to see what you should do right now."Azarenka only dropped three games in a 6-2, 6-1 defeat of Swiss qualifier Stefanie Voegele and takes on former world number one Jelena Jankovic in the next round. French Open semi-finalist Bartoli beat Slovenia's Polona Hercog 6-3, 6-3 to set up a showdown with Australian Jelena Dokic.