Harimoto, a quarter-finallist at last year's World Championships, has long been considered a potential threat for the top Chinese stars but his performance today on home courts represented a triumphant coming of age.

The teenager moved 3-0 ahead before withstanding a fightback to triumph 11-8, 11-9, 11-7, 3-11, 2-11, 11-6 at the Kitakyushu City General Gymnasium.

Ma was the defending champion and winner of last year's China Open and is considered by many to be the greatest player ever to compete in the sport.

Zhang Jike, the 2011 and 2013 world champion and a rival for that accolade, ensured Chinese will be represented in the semi-finals.

He battled past fellow countryman Liang Jingkun 8-11, 11-9, 2-11, 11-7, 11-3, 2-11, 15-13 before a 9-11, 11-7, 9-11, 8-11, 13-11, 11-7, 11-7 quarter-final victory over Japan's Jin Ueda. 

Harimoto will now face South Korea's world bronze medallist Lee Sang-su, a 11-3, 8-11, 9-11, 3-11, 11-8, 11-5, 11-4 winner from 1-3 down against Chinese Taipei veteran Chuang Chih-Yuan.

Germany's top seed Timo Boll beat Japan's Kenta Matsudaira 12-14, 13-11, 11-3, 11-7, 11-9 to set up a mouth-watering semi-final with Zhang.

Chen Xingtong was the star of the day in the women's singles as the Chinese player beat Japanese top seed Kasumi Ishikawa 11-3, 11-4, 10-12, 9-11, 11-7, 11-9.

Mima Ito ensured a home presence in the last-four by beating Chinese Taipei's Cheng I-Ching 11-3, 11-7, 11-13, 8-11, 11-3, 11-6.

Liu Shiwen and Wang Manyu set-up an all-Chinese semi-final in the other half of the draw.

Liu breezed past Japan's Miu Hirano 11-4, 11-7, 11-3, 11-4 while Wang overcame Hong Kong's Lee Ho Ching 11-6, 11-7, 11-8, 7-11, 11-9 and then China's Mu Zi 11-5, 11-9, 11-8, 11-8.