Chinese badminton players romped into the quarter-finals of the Thomas and Uber Cup as the world No. 1 ranked Lee Chong Wei pulled out of the tournament with a torn ligament.

Lin Dan of China returns a shot during the Thomas and Uber Cup in Wuhan on May 22.[Photo/Xinhua]

The Chinese men's side, the reigning Thomas Cup champions, clinched an easy 5-0 win over Indonesia in Group A.

Lin Dan brushed aside Simon Santoso 21-10, 21-17 before Cai Yun/Fu Haifeng extended the host's lead to 2-0 by beating Kido Markis/Septano Bona 21-14, 21-8.

Chen Long scored the winning point by crushing Sugiarto Tommy 21-12, 21-16 before Shen Ye/Hong Wei and Chen Jin completed the tally.

Thanks to the two withdrawals from Indonesia, the Chinese women marched into the Uber Cup quarter-finals with a 5-0 victory.

Malaysia's prospect in the Thomas Cup suffered a double whammy in Tuesday's match, in which the badminton powerhouse not only lost its leader Lee Chong Wei who sprained his ankle, but also lost the top seed of Group C after losing 3-2 to Denmark.

"Lee is very sad and worried about the Olympics. His injury definitely casts a shadow on our prospect," said Rashid Sidek, the singles coach of Malaysia.

Lee, a hot favorite for Olympic gold, was diagnosed with a torn ligament and decided to return to Malaysia on Wednesday. He has to rest at least three weeks.

Following the victory, Denmark is seeded for the quarterfinal draw as group champion while Malaysia is unseeded as the runner-up.

In the other group action, Japan overwhelmed Russia 5-0 and South Korea edged past Germany 3-2. All of these four teams go through to the quarter-finals

In the Uber Cup, South Korea and Germany advanced into the top eight from Group C. The other quarter-final tickets were taken by Indonesia, Japan, Denmark, Chinese Taipei and Thailand.