The picture taken of China's badminton lovebirds, Lin Dan and Xie Xingfang, after they claimed their respective singles titles at the 2006 World Championships will only be a sweet memory from now on.

Xie's loss at the quarterfinal stage of China's 11th National Games signaled the end of the former world No 1's playing career.

However, her boyfriend, "Super Dan", will battle on and has his sights set on defending his Olympic title at the 2012 London Games. He successfully defended his National Games championship on Sunday.

"The deep love I have for badminton is the motivation for me to keep making progress," said Lin, who defeated national teammate Bao Chunlai 21-11, 21-3 in a 35-minute final at the National Games. "Now, I will start all over again and regard myself as a freshman who is eager to train and compete every day. I will try to work hard and save my best form for the London Games."

Sunday's clash was a replay of the National Games' final four years ago where Lin thrashed Bao 15-10, 15-2.

The victory made Lin the second men's player to defend a National Games singles title. The first was Lin's coach, Tang Xianhu, who claimed gold medals at the second and third National Games.

"In order to win this gold I had to shoulder a lot of pressure. I'm so lucky that I did that and won," Lin said.

With 12 world champion titles to his name, national coach Li Yongbo regards Lin as the best men's player of the past decade.

"Lin is only 26 and has won 12 world champion titles. He has been the best men's singles players in the world for nearly 10 years," Li said. "I believe he should be able to maintain his good form in the coming years. He is capable of competing strongly at the London Games and could step on to the highest podium again."

However, Lin will have to do that without the company of his girlfriend.

Her loss to current world No 1 Wang Lin, 21-15, 21-16, in the quarterfinals of the National Games, was the 29-year-old's swansong.

It is believed Xie will return to Guangdong province to take up a position on the Guangzhou Asian Games organizing committee. She is also believed to be considering taking up college studies.

"I have submitted my resignation and it has been accepted," said Xie, a dual world champion in 2006 and 2007, after her final match. "After the National Games, I will take a break to prepare myself mentally and physically for a new life."

The lovebirds have been in the spotlight since their romance became known in 2004.

Their most memorable moment came in 2006 when they won the World Championship singles titles in Madrid.

Lin considered Xie's retirement "very normal".

"Every athlete will retire one day. Whatever she chooses to do after she retires, I am on her side," Lin said.

"Her retirement will have no affect on me. The only difference is that we can't train together every day or compete at the same event. But I can understand her choice. People have to leave themselves some space to accept new things in certain periods of life. She is at that period now."