By Shrivathsa Sridhar MELBOURNE (Reuters) -Zheng Qinwen was the first big name to exit the women's draw at the Australian Open on Wednesday after the Olympic champion was stunned by Laura Siegemund while top seed Aryna Sabalenka made heavy weather of her second-round match before going through.

Last year's runner-up Zheng Qinwen was knocked out of the Australian Open on Wednesday in the biggest shock so far but defending champion Aryna Sabalenka and two-time winner Naomi Osaka

Last year's runner-up Zheng Qinwen was knocked out of the Australian Open on Wednesday in the biggest shock so far while defending champion Aryna Sabalenka had to battle serve jitters to make the third round.

Aryna Sabalenka said early exits by big names at the Australian Open would not make her title defence any easier after the top seed saw one of her main title rivals go out in the second round with Zheng Qinwen's defeat by world number 97 Laura Siegemund.