MELBOURNE (AFP) - Struggling Sloane Stephens became a first-round casualty at the Australian Open on Monday, crashing in straight sets to Chinese qualifier Wang Qiang.

The 24th seed, who burst onto the scene in making the Melbourne Park semi-finals in 2013, was no match for the little-known Wang, who was a comfortable 6-3, 6-3 winner on Hisense Arena.

Stephens, who also fell at the first hurdle last year, came into the tournament on the back of claiming her second WTA tour title at the Auckland Classic this month.

But the American, once ranked 11th in the world, then pulled out of the Hobart International citing an unspecified illness.

Wang, ranked 102nd and China's No. 2 behind Zheng Saisai, will next play Germany's Anna-Lena Friedsam, who floored Spain's Lourdes Dominguez Lino in three sets.