Russia's Tatyana Lysenko, who watched the 2008 Olympics on TV while serving a two-year doping ban, won the women's hammer gold with an Olympic record throw of 78.18 metres.

Lysenko, who won the world championship title last year, beat the old Olympic record of 76.34 set by Askana Miankova in Beijing with her first throw of the night, 77.56m, then improved it with her fifth.

Anita Wlodarczyk of Poland took silver with 77.60 and China's Zhang Wenxiu a second successive bronze on 76.34.

Sophie Hitchon, a former ballet dancer, broke the British record in qualifying but struggled in the final and finished 12th.