BIRMINGHAM: Top seed Li Xuerui, the Olympic champion, and third-seeded world champion Wang Yihan crashed out of the All-England Open at the first round stage on Wednesday.

On a miserable day for China, Li, the defending All-England champion and regarded as the sport's outstanding woman player after her Olympic triumph, went down 21-18, 21-18 to Bae Yeon Ju, the world number 13 from South Korea.

The Chinese player did not blame either the wind drift or having to face such a high quality opponent in the first round for her defeat.

"It was personal performance issues, too many mistakes, nothing else," she said.

Li's defeat should have opened up a better chance for her Chinese compatriot Wang Yihan, the number three seed and former All-England champion, reaching the final.

But Wang became the latest Chinese casualty when she lost 21-12, 21-19 to Lindaweni Fanetri, the world number 18 from Indonesia, who had won only one match out of three in Super Series tournaments this year.

Wang's defeat means the two top women's singles title contenders from the sport's leading nation have both gone out in the first round.

Later, two other Chinese seeds were beaten in the first round, both in the men's singles.

The most surprising was the defeat of the third-seeded Du Pengyu, the runner-up in the World Super Series finals, who went down 21-17,15-21, 21-18 to Chou Tien Chen, the world number 28 from Taiwan, who scored the finest victory of his career.

Earlier Hu Yun, the sixth seed, also failed to survive a long match, leading 19-17 in the final game and still losing 21-16, 11-21, 23-21 to Tanongsak Saensomboonsak, a qualifier from Thailand.