Olympic volunteers won their own gold today -- finding a lost wedding ring in a huge sand pit at the women's beach volleyball.

When Olympic champion Kerri Walsh jumped up to block the ball in her opening match, the gold band flew off her finger.

The ever-smiling American, who is married to fellow beach volleyball player Casey Jennings, carried on as if nothing had happened but after the end of the morning session volunteers were dispatched to find the ring.

Armed with metal detectors, they combed through the deep sand. Finally there was a beep and one of them, Song Zhendong, dug the ring out.

"I try my best to help others. I feel honoured to have found Kerri Walsh's wedding ring and I don't need any special thanks," said Ms Song.