CHRISSY Ohuruogu is waiting to fight another day after surprisingly slumping to sixth place over 400 metres at the Exxon Mobil Bislett Games in Oslo.

The Olympic champion never looked like the woman who won the gold medal in Beijing when on a rainsoaked track she struggled to match the fast early pace in a race won by arch-rival Sanya Richards.

Richards is unbeaten this season and despite the wet conditions which delayed the start to the meeting’s main programme, the American displayed magnificent form.

The 24-year-old, who finished third behind Ohuruogu in the Bird’s Nest stadium last August, easily stormed to her second Golden League success of the year.

Richards coped with the conditions to lower her world-leading time for this year to 49.23secs ahead of Olympic silver medallist Shericka Williams (49.98secs) and Amantle Montsho (50.71).

‘‘I did not expect to run the world lead after the storm,’’ said Richards, determined to win her first major global title at next month’s World Championships in Berlin.

Ohuruogu refused to blame a bug which forced her to pull out of a recent meeting in Milan.

‘‘I thought I was in good shape, so I don’t really know what happened,’’ said Ohuruogu who clocked an ordinary 51.19, 0.05 slower than in her opening race of the season last month in Montreuilsous-Bois.