He conceded a walkover to China’s Li Shi Feng while leading 15-10, after winning the first game by 22-20, in the Group A match.

The injury nullifies the results of his group stage matches, and will ensure that Denmark’s Anders Antonsen and Shi Feng will qualify from Group A for the semi-finals.

An official announcement is expected later.

According to a World Tour official, any player or pair who retires due to injuries or pulls out for other reasons will lead to the cancellation of their results in all matches played at the group stages. The rule is aimed at ensuring a level playing field, the official said.

Zii Jia, the world No 6, injured his ankle while retrieving a drop shot from his China rival.

Antonsen is scheduled to play Taiwan’s Chou Tien Chen in his last group tie later today. He will top the group if he wins.

Zii Jia will take home US$15,000 by virtue of being placed fourth in his group.