Tzu Wei Wang of Taiwan beat Olympic champion Chen Long ©Getty Images

Olympic champion Chen Long was defeated by Taiwan's Tzu Wei Wang today in the semi-finals of the Badminton World Federation (BWF) German Open in Mülheim.

The 14th seed triumphed 21-18, 8-21, 21-18 over the Chinese star in a match lasting 64 minutes,

Tzu will now face team-mate Chou Tien Chen in the final.

The sixth seed overcame Takuma Ueda of Japan 21-17, 21-11 in today's other semi-final at the Innogy Sporthalle.

Spain's Carolina Marin ensured it was not a wholly unsuccessful day for reigning Olympic champions, however, by comfortably progressing into the women's singles final.

Chou Tien Chen set-up an all-Taiwanese men's singles final ©Getty Images
Chou Tien Chen set-up an all-Taiwanese men's singles final ©Getty Images

She lost the second set but recovered to beat Japan's Minatsu Mitani 21-10, 17-21, 21-18.

Marin will now face another Japanese player in Akane Yamaguchi in the final.

The second seed overcame Zhang Beiwen of the United States 24-22, 21-19.

Finals are all scheduled for tomorrow.