Lin Dan, right, celebrates with his wide Xie Xingfang after winning his fifth world champion during Badminton World Championship final in Guangzhou, Guangdong province, Aug 11, 2013. [Photo/Xinhua]

GUANGZHOU, China - China's badminton superstar Lin Dan won a thrilling final for his fifth world champion here on Sunday over Lee Chong Wei, who abandoned his game in the decider due to injury.

Coming back from one set down, the defending champion, who entered the tournament with a wild card, led the score board 16-21, 21-13, 20-17 when Lee called the game off with an injured knee.

Lee, who lost both Beijing and London Olympic men's singles finals to Lin as well as that of the last world championships, was forced to halt the match twice for medical help.

Lin cared about Lee's injury and had twice approached to see if Lee could hang on before he helped the medical staff to carry the arch-rival and old friend of his off the court.

Lee was sent to hospital directly while his fans cheered and applauded for him outside of the Tianhe Gymnasium.

"I saw his leg cramp at that time. He really cannot persist, otherwise I think he will definitely not give up," said Lin after the match.

"I want to thank my great opponent, without whom I will never know where my potential is. Thank you, Lee."

After winning a back-to-back Olympic title a year ago in London, the 29-year-old Lin took a gap year to enjoy family time. He dropped to No 286 in the world rankings recently.

His wife and former teammate Xie Xingfang, who showed up off-court as a guest seat broadcaster, gave Lin a kiss on the sideline while he celebrated his fifth crown at the world championships.

"Many people don't predict such an ending, but I think both of us have tried our best. We are both 30 year-old. One year after the London Olympics, we can still meet in the final. We have proved our value. There are no loser between us. We truly love badminton," added Lin.

Lin Dan, right, helps injured Lee Chong Wei, left, during their Badminton World Championship final in Guangzhou, Guangdong province, Aug 11, 2013. [Photo/icpress.cn]