Four-times Olympic rowing champion Matthew Pinsent announced his retirement from rowing.

The 34-year-old, unbeaten at a major championships for 12 years until 2003, won his fourth gold medal amid emotional scenes in Athens.

"I am announcing today that Athens was my last rowing race in a Great Britain vest. I know that it is a feeling of sadness that surrounds a retirement but I feel anything but sad," Pinsent told a news conference on Tuesday.

"I feel happier and more at peace with my sport and my athletic performance than at any other point in my career."

Pinsent said he had lost the desire to train since his Olympic triumph in August.

"After Sydney I was happy to throw myself into a four-year campaign. After Athens it has been different, I think my body knows it is done.

"I always said I would retire after Athens and so it has proved. I will be cheering you (his team mates) on from the beer tent, perhaps a bit drunk and a bit jealous."

Pinsent joined forces with Steve Redgrave at 19 and spent much of his career in Redgrave's shadow.

After helping Redgrave win three of his five consecutive Olympic titles, Pinsent achieved probably the greatest moment of his career by winning the coxless four gold medal at the Athens Games in a photo finish.

After a difficult season marred by injury and crew changes, Pinsent, James Cracknell, Ed Coode and Steve Williams held off favourites and world champions Canada to take the gold by 0.08 of a second.

As his three ecstatic team mates bellowed the national anthem, the six-foot-five-inch old-Etonian broke down and sobbed at the medal ceremony.

Pinsent later told friends he was worried his public outpouring of emotion would overshadow his crew mates' achievement.

Like Redgrave, Pinsent's success has been based more on his power and commitment than elegant technique.

Following Redgrave's retirement in 2000, Pinsent and Cracknell opted to compete in the coxless pairs but could not find the consistency they needed and finished a poor fourth at the 2003 world championships.

After that upset the pair controversially moved into the four, displacing two others, and drew criticism that they were avoiding a potentially tougher challenge. However, the manner of their victory in Athens captivated Britain.