Chinese Wu Yunyong defeated Jonassen, second seed from Denmark, in the opening day of China Open Badminton.
Chinese Wu Yunyong produced the biggest upset, wiping out Jonassen Kenneth, second seed from Denmark, by straight sets in the opening day's first round of the 250,000 US dollars China Open badminton championships on Tuesday.
In bidding farewell to the tournament which is to run until November 16, Jonassen, a semi-finalist in the Chinese Taipei Open, explained that a three-week honeymoon leaves no time for his practice.
"I'm only 60% percent of my best form. It's normal to have lost this game," said Jonassen.
Eighth-seeded Dannish Kaldau Niels Christianalso, winner of the German Open last year, also made early exit when he lost to Chinese Zhu Weilun, a quarterfinalist in last year's China Open, in their first tie.
South Korean Park Tae Sang who beat world champion Xia Xuanze of China twice this year, improved his record to 2-0 against 14th-seeded Japanese Hidetaka Yamada.
Top seed Chen Hong of China received a bye today, and will play his first tough fight against Dannish fourth seed Peter Gade who beat two-time gold medalist Tooru Matsumoto of Japan.