China's leading men's singles Lin Dan and Chen Jin both pulled out of the Hong Kong Badminton Open here on Friday before the quarterfinals, a bit later than they did here last year.
Xia Xuanze, men's singles coach of the Chinese national team, told reporters that Lin felt uncomfortable in his waist this morning while Chen suffered a foot injury in Thursday's second round match.
"Lin is too tired after so many matches in the past few weeks," he added.
In last year's Hong Kong Open, Lin quit without playing a single match while Chen gave up during the first round match due to an injury. Lin also played two rounds and called a quit before the quarterfinals in the China Open earlier this month.
Their retirement sent Vietnam's Nguyen Tien Minh and the top seed Lee Chong Wei from Malaysia directly into the semifinals.
The 21-year-old Chen Long became the only Chinese player left in the men's singles top four. The 7th seed came from one set behind to edge out South Korea's veteran Lee Hyun Il in a 77-minute clash. Chen was caught up from a comfortable lead of 18-13 in the third set before he recovered to seal the victory by 21-19.
Chen, winning his first super series title last week in China Open, will face the 3rd seed Taufik Hidayat of Indonesia in the semifinals.
The men's doubles saw another walkover of the day. Indonesia's Olympic Champion Markis Kido/Hendra Setiawan were sent into the semifinals by the retirement of compatriots Alvent Yulianto Chandra/Hendra Aprida Gunawan.
The 2nd seed duo will play against South Korea's Jung Jae Sung/Lee Yong Dae for a final spot. Jung and Lee overcame China's World Champions Cai Yun/Fu Haifeng for the fourth time in a month, 21-19, 21-16.
"They have improved a lot in the past couple of years," said Cai. "Comparing with the other top pairs in the world, they don't have a particular shortcoming and they are also the youngest. I would say they have been the biggest threat to us toward the London Olympics."
Another South Korean pair Ko Sung Hyun/Yoo Yeon Seong will compete with Howard Bach/Tony Gunawan in the semifinals.
In the women's singles, the third seed Wang Shixian from China, newly crowned at the Guangzhou Asian Games, beat Thai teenager Inthanon Ratchanok in straight sets. The 15-year-old rising star managed to lead into the interval of the second set but failed to keep pushing her elite opponent.
"I am not strong enough to win such a tournament yet," said Ratchanok. "It is more important for me to get experiences."
Top seed Wang Xin ousted veteran Pi Hongyan from France in two sets to set up a third clash with compatriot Wang Shixian in three weeks after the Asian Games and China Open. Wang Xin, 25, lost to her younger teammate Wang Shixian, 20, twice both by 2-0 in the Asiad final and China Open semifinals.
Another Chinese woman Jiang Yanjiao, however, was knocked out by Germany's Juliane Schenk 21-14, 16-21, 21-12 in over an hour. Jiang, winning the China Open for the third consecutive time only five days earlier, said she has been short of energy coming to Hong Kong.
The 6th seed Schenk will play against 2nd seed Saina Nehwal from India for the final.
Women's top ranked doubles Cheng Wen-hsing and Chien Yu-chin from Chinese Taipei will meet Russian duo Valeria Sorokina and Nina Vislova in the semifinals while another match will be played between China's two pairs, Pan Pan/Tian Qing and Wang Xiaoli/Yu Yang.
For the mixed doubles event, top seed Robert Mateusiak/Nadiezda Zieba from Poland were stopped by Joachim Fischer Nielsen/Christinna Pedersen from Denmark. China's two pairs, 5th seed Zhang Nan/Zhao Yunlei and Xu Chen/Yu Yang, both outdid South Korean duos in three sets. Chinese Taipei's Lee Sheng-mu and Chien Yu-chin booked another semifinal position.