Russia claimed a surprise victory in the women's 4x100m relay as favourites Jamaica and Great Britain failed to get the baton round cleanly.
Jamaica, who swept the medals in the 100m final, failed to hand the baton on in the second changeover between Sherone Simpson and Kerron Stewart.
At the same time, there was a mix-up in the changeover between Britain's Montell Douglas and Emily Freeman.
With the field reduced, Belgium took silver with Nigeria claiming bronze.
