LONDON - Chinese swimming sensation Sun Yang upset defending champion South Korean Park Tae Hwan in men's 400m freestyle to win a historic Olympic swimming gold for China on Saturday.

Sun was behind Park in the first 200m, and narrowed the gap in the third 100m. He put on a devastating burst over the last 100m to overtake Park at 3:40.14, setting a new Olympic record.

Sun Yang of China celebrates after winning men's swimming 400m Freestyle Final competition at London 2012 Olympic Games in London, Britain, on July 28, 2012. Sun Yang won gold medal in this event. [Photo/Xinhua]

Park posted 3:42.06 to settle for a silver and Peter Vanderkaay from the United States finished 3:44.69 to take a bronze.

Sun was the first male Chinese swimmer to claim an Olympic gold.

"I felt the pressure because my coach is not in good health, so maybe he has been under more pressure than I am. I want to dedicate this victory to him," said Sun, who starred at last year's Shanghai World Championships as he smashed Grant Hackett's decade-old 1,500m world record .

"I have swum my personal best time and I want to use this swim to tell the South Koreans (who were angry after Park was disqualified this morning) something. I want to show that we are good swimmers and we do not need to do anything other than swim in order to win," said a confident Sun.

Park was initially disqualified by a judge on the pool deck for a false start in the morning heats, after which South Korean media accused so-called referee conspiracy by a Chinese judge. However, it turned out to be a rumor as no Chinese judge was involved in the event. Later, Park was reinstated in the final after the FINA Jury of Appeal examined the protest lodged by the Korean Swimming Federation and made the decision based on the recommendation of the FINA Technical Swimming Commission.

Sun's performance in evening's final underlined his supremacy in the event.

Park, who hardly missed the final, said he was disappointed with a silver because he had waited a long time for this race.

"I tried my best in the race. I don't want to say that what happened with having been disqualified was bad for my performance, but it was," he said.

"I lost the race, but I am glad that it was an Asian who won. It is something we can all be proud of," Park said.

The gold medal is one of the most eagerly awaited clashes between Park and Sun. In London, Sun finally succeeded in the revenge after losses to Park in the 400m freestyle at the 2011 Shanghai World Championships and the 2010 Guangzhou Asian Games.