Thursday, August 21, 2008 - 3:59 PM

Australia has picked up a silver medal in Olympic sailing on the final day of yachting in the Beijing Games.

World champions Darren Bundock and Glenn Ashby had to finish two places ahead of the Spanish crew of Fernando Echavarri and Anton Paz to secure gold in the Tornados.

But in windy conditions off Qindao both teams were placed back in the field, leaving Spain to pick up the gold and Australia the silver.

The medal is Australia's third for sailing in the Beijing games, after gold in the men's and women's 470 class.

These games could be the last Olympic appearance for the Tornadoes - the class has been dropped from the sailing program for the London games in 2012.

Torrential rain in Beijing this morning forced organisers to postpone today's Olympic semi-finals of the BMX event.

But most events went ahead as scheduled despite the poor weather.

Australian athlete Jarrod Bannister struggled with the conditions, but still qualified for Saturday's final of the men's javelin.

Bannister managed a throw of 79 metres and 79 centimetres, to squeeze through to the 12-man final in 11th spot.

Australian diver Melissa Wu has qualified for tonight's final of the women's 10 metre platform.

Americans Kerri Walsh and Misty May-Treanor have defended the title they won in Athens, by winning Gold in the women's beach volleyball.

Russian athlete Olga Kaniskina has won gold in the women's 20 kilometre walk, while Australian Jane Saville was 20th.

The Netherlands' Maarten van der Weijden took the gold medal in a thrilling finish to the men's 10 kilometre open water swim, just ahead of Britain's David Davies and German Thomas Lurz.

Time is running out to put a dent in China's runaway lead on the Olympic medal tally board.

With four days of competition to go, the host nation has almost twice the amount of gold medals won by the 2nd placed nation, the United States.

Australia's athletes are not done yet, with the men's hockey team and the women's basketball side closing in on their respective finals.