The 25-year-old battled Canada's Skylar Park in the women's under-57 kilograms final in the Chinese city last week and took the first round in the best of three format.

In the second, Kiani led going into the final second but Park struck to take the contest into a third round.

History then repeated as, again with one second remaining, the Iranian lost her lead thanks to a devastating attack from Park.

It meant that two chances to win gold evaporated right at the death and Kiani dropped to her knees in dismay at the end of the final.

"Since yesterday, I have seen that moment running through my mind more than 100 times," she said.

"What could I have done to change the result?

"Taekwondo is a sport of the moment and I have won many matches like that, I have changed the result.

"In the future, I will be more careful about the last moment."

Kiani, a Tokyo 2020 Olympian, won gold in the women's under-53kg division at the World Championships in Baku in May and June.

She has stepped up a weight to under-57kg and says she feels more comfortable in the heavier division with new coach Minoo Madah.  

In Tokyo, she was notably beaten in the first round by Kimia Alizadeh - a Rio 2016 bronze medallist who had defected from Iran after highlighting the treatment of women.

Alizadeh was competing for the Refugee Olympic Team and without a headscarf - mandatory for women in Iran.