BANGKOK (AFP) - China's top-ranked player Peng Shuai tumbled out of the Thailand Pattaya Open in a three-set loss to Japan's Misaki Doi, as two-time champion Vera Zvonareva advanced to the third round also at the expense of a Chinese player.

Top seeded Peng Shuai, a hot favourite in a weak Pattaya field after making it to the last 16 at the Australian Open, went down 3-6, 6-2, 2-6 to Doi, the world No. 104.

The unfancied left-hander stunned her Chinese rival by taking the first set. She stumbled in the second but regained her composure in the third, relying on her first serve returns to see out the match.

Zvonareva, who won back-to-back Pattaya titles in 2009 and 2010, moved into the third round with a hard-fought 7-6, 6-3 win over eight seed Zhang Shuai.

The 30-year-old Russian is on something of a comeback trail, after injury and poor form saw her drop from a top-10 career high in 2010 to a current WTA ranking of 189th.