Chinese women's number one Li Na ousted last year's runner-up Francesca Schiavone of Italy in straight sets in the opening round at the Sydney international tennis tournament on Sunday.

The world No. 21 registered 75 percent first serves to knock out Schiavone 6-4, 7-5 in 94 minutes.

Li will now face the winner of sixth Russian seed Elena Dementieva or Japan's Ai Sugiyama in the second round.

Highly-rated Serb Ana Ivanovic cruised to a 6-3, 6-4 win over Australian Casey Dellacqua.

In other matches, Israel's Shahar Peer beat Anna-Lena Groenefeld of Germany 6-4, 6-2 and eighth-seed Nicole Vaidisova of the Czech Republic defeated Slovakian Daniela Hantuchova 6-1, 6-4.