LIUZHOU, Guangxi - China's "Super Dan" Lin Dan completed his super "Grand Slam" after beating Chen Long in the final at the BWF World Superseries Finals here on Sunday.

Meanwhile, defending champions Mathias Boe and Carsten Mogensen of Denmark denied China's clean-sweep by defeating Chinese young pair Chai Biao and Guo Zhendong in straight sets in the men's doubles.

Lin Dan, arguably the best shuttler in the world, has won four world titles, and is also the reigning Olympic and Asian Games champion as well as the Asian championships gold medalist.

However, he had never participated in the Finals before. This time in Liuzhou, a southern Chinese city, he finally completed his collection of trophies.

The 29-year-old southpaw met little challenge from his teammate Chen, who stunned world No.1 Lee Chong Wei of Malaysia in Saturday's semifinals, before wining the final 21-12, 21-16.

"In fact, I didn't care too much about the results. The important thing is Chinese team secured the men's singles gold medal after the semifinals," said Lin, who won all five matches in the year-ending elite tournament.

In women's singles, newly-crowned world champion Wang Yihan of China came from behind to defeat India's Saina Nehwal, India, 18-21, 21-13, 21-13 and capped a brilliant year with the World Superseries Finals title.

It wasn't until May that Wang won her first tournament -- the Malaysia Open Grand Prix -- in 2011, but she found back the rhythm in the second half of the year as she won the world championships and the Asian championships titles.

"My dream is to win the gold medal in next year's Olympics," said the 23-year-old Wang.

In men's doubles, Boe and Mogensen saved six set points in a row to take the first set 25-23, and continued their momentum in the second set to conclude the match against Chai and Guo 21-7.

"When we led 20-17 in the first set, they (Boe and Mogensen) made some changes in service while we were too eager to win the set. After losing the first set, we lost the rhythm," said Chai.

BWF Players of the Year Yu Yang and Wang Xiaoli were too good for South Korean pair Ha Jung Eun and Kim Min Jung, winning in straight sets 21-8, 21-12 in just 33 minutes.

The Chinese pair have made 13 consecutive finals appearances with seven Superseries titles to their name in 2011.

"To be honest, we are the pair to beat in women's doubles nowadays. The biggest opponents for us are ourselves as injuries and downturns troubled us sometimes in the season," said Yu.

In mixed doubles, world No. 1 Zhang Nan and Zhao Yunlei, who defeated their teammates Xu Chen and Ma Jin in three sets in the group stage, did it again as they won the final 21-13, 21-15.