Lee Chong Wei Suffer Fatigue in Japan Super Series

Defending champions Lee Chong Wei and Tine Rasmussen struggled into the Japan Open quarter-finals Thursday with the Malaysian world number one complaining of post-Olympics fatigue.

Lee survived a second-game fightback by local hope Sho Sasaki to win 21-7, 22-20 while Denmark's Rasmussen came from behind to beat China's Wang Lin 10-21, 21-11, 21-18.

Lee, who lost last month's Olympic final to China's Lin Dan, had also looked unconvincing in his first-round 25-23, 21-8 win over unfancied Chinese Zhu Weilun.

"I still feel tired as I only took a week off after the Olympics and prepared for this tournament as I wanted to take part in as many events as possible," the 25-year-old.

"I lost my concentration and wound down after an 11-3 lead in the second game. That's why I was overtaken that way."

Lee faces a first ever match-up with China's 150th-ranked Qiu Yanbo in the last eight.

"I may recover from fatigue somewhat in due course. But whether or not I am tired, I want to take one match at a time in a careful manner," he said.

Qiu progressed when fifth-seeded Indonesian Simon Santoso pulled out with back pain when 21-10, 8-6 down. Santoso injured his back in winning last week's Taiwan Open.

In other men's matches, Indonesian second seed Sony Dwi Kuncoro outclassed Sairul Amar Ayob 21-8, 21-7 to face another Malaysian, Muhammad Roslin Hashim, who beat Thailand's Boonsak Ponsana 21-17, 21-15.

Ex-Olympic champion Taufik Hidayat beat Denmark's Jan Jorgensen 21-10, 21-12 to set up a quarter-final with European championship runner-up Joachim Persson, who overcame Tommy Sugiarto 21-14, 21-15.

Rasmussen, the All-England winner and women's second seed, needed 48 minutes to overcome Wang as top-seeded Lu Lan of China made short work of Japan's Kaori Imabeppu 21-7, 21-8.

"I had to work really hard and, maybe, I didn't play too clever," said Rasmussen, 29, whose career has blossomed after winning her first major title here last year.

"I think I was against the (air conditioners') wind in the first game and I didn't get enough length. So Wang could just stand on it and put pressure on me," Rasmussen added.

Rasmussen faces a tough quarter-final against Hong Kong's world silver medallist Wang Chen, who reached the last eight on a walkover against China's Jiang Yanjiao.

"I think it's going to be a 50-50, open-ended match," said the Dane, who has already won three Super Series events this year in Malaysia, England and Singapore.

"I have to adjust many things and I have to play better if I want to win."

The 200,000-dollar Japan Open is the seventh leg of badminton's 12-round Super Series.