Zou Shiming retains his light fly weight Olympic boxing title in London.

China's Zou Shiming has retained his light fly weight Olympic boxing title after claiming victory in the gold medal match against Thailand's Kaeo Pongprayoon. Zou, who edged the Irish fighter Paddy Barnes on Friday's semifinal, became the first  boxer who has retained the title of this category.

Zou, the top seed and world champion, followed up his success in Beijing four years ago with a 13-10 success over Pongprayoon.

The 31-year-old veteran took the advantage in the first round 2-1, in which both fighters seemed reluctant to attack first.

The second round was much hotter than the first one, Zou defended his side better than his opponent, ending the second quarter 4-3.

Pongprayoon made effort in the third round to pull the score back, but Zou was more efficient to end the third and final round with 7-6, pocketing his third medal and second gold at his three Olympic Games.

The decision was met by boos from the crowd and Pongprayoon collapsed to the floor when the decision was announced before leaving the ring in tears.

"Every match was difficult, both for me and my opponents," said Zou.

"Second gold medal is great for me. I'm enjoying it."

Zou was known as the number one fighter in China, especially after he claimed the bronze medal at 2004 Olympics. He pocketed three titles from 2005 to 2011 at the World Championships, and those trophies put a lot of pressure on his shoulder.

It was possibly the final Olympic show for the father of a one-year-old son. He was to spend more time with his wife and son after going back home.

"I've promised them I would bring back home another Olympics gold, and today I fulfilled my promise," said Zou.

Zou wasn't on his top form before the final. He failed to harvest overwhelming victory in every of his three previous matches, and his breathtaking semifinal arose the concern of the Chinese boxing fans.

"There was too much pressure. Luckily I won the match after all. All I want to do now is to have a very very good rest, " said Zou .

Pongprayoon said: "I feel that I won and I could see that the crowd thought I won. I don't know why I lost. I've lost to him twice before and both times I think I should have won.

"I am still really happy, still very proud to bring back a silver medal." he said.