Beijing - Olga Kaniskina of Russia led from start to finish on Thursday to win the women's 20 kilometres race walk Olympic gold in atrocious conditions.

The world champion clocked 1 hour 26 minutes 31 seconds in driving rain on a course outside the Bird's Nest stadium.

Kjersti Platzer of Norway got the silver as at Sydney 2000 in 1.27:07 and then took almost longer to find a Norwegian flag in the stadium for her lap of honour. Elisa Rigaudo claimed bronze for Italy in 1:27:12 hours.

"I have won at championships but an Olympic medal is more difficult because all the competitors are here. I was in good condition," said Kaniskina.

The walkers were undeterred by the rain.

"The weather had no influence on me. It was better than a sunny and hot day," said Kaniskina. Platzer agreed: "For endurance athletes rain doesn't matter."

But the torrential rain affected the morning schedule as slippery conditions forced organizers to put back the women's high jump and men's javelin qualifying round because competition would have been unsafe.

When the weather finally got better world champion Blanka Vlasic of Croatia was among 15 women who cleared 1.93m to qualify for the high jump final.

"I didn't want to waste my energy so I gave it 50 per cent," said Vlasic.

"In these circumstances, it's normal that things aren't so easy," added the 24-year-old, referring to the weather.

"Everyone sees me as a favourite because I am in top shape but nothing is for certain in sport."

There were also no upsets in the javelin qualifiers even though the 2004 gold medallist Andreas Thorkildsen of Norway only just made it with 79.85m. Vadims Vasilevskis of Latvia had the leading throw with 83.51m.

The decathlon got underway with American favourite Bryan Clay taking an early lead with a 100m run in 10.44 seconds and a long jump of 7.78m for 1,994 points.

Compatriot Trey Hardee followed on 1,960 points with Ukraine's Oleksiy Kasyanov third on 1,918 points. The shot put, high jump and 400m were set for later on the event's opening day.

Early casualties included former world champion Tom Pappas of the US and Dmitriy Karpov of Kazakhstan, a bronze medallist from the 2003 worlds and 2004 Olympics.

The day's other finals, women's 200m and javelin as well as the men's 400m, 110m hurdles and triple jump were scheduled for the evening.