Former top-ranked Australian Samantha Stosur has slumped to yet another first-round exit after blowing a one-set lead against China’s Han Xinyun at the Guangzhou International.

The 2011 US Open champion played her first match since the French Open last week in Tokyo, where she was also eliminated at the first hurdle by Spain’s Sara Sorribes Tormo.

Stosur looked on course to go deep into the draw at Roland Garros, where she made her first grand slam final in 2010, before a wrist injury struck in a round-of-16 loss to eventual champion Jelena Ostapenko. The 33-year-old subsequently withdrew from Wimbledon and the US Open.

She took the first set in China on Tuesday in a tiebreak but floundered in the second before losing a tight decider to go down 6-7 (7-6) 6-3 7-5.

The news was little better for fellow Australian Arina Rodionova, who lost 7-6 (6-3) 3-6 6-0 to Evgeniya Rodina of Russia but Queenslander Lizette Cabrera proved too strong for China’s Gao Xinyu, winning 2-6 6-1 6-3.

Chinese second seed Zhang Shuai made light work of countrywoman You Xiaodi, winning 6-1 6-0 while sixth seed Alize Cornet of France recovered after dropping the first set to beat American Bernarda Pera.

Belgian fifth seed Elise Mertens was the biggest casualty, losing in straight sets to China’s Wang Yafan.