South Africa’s Caster Semenya brushes off doubters to win 800m gold in Rio as controversy murmurs on

Controversial South African runner Caster Semenya produced a devastating sprint finish to claim the Olympic 800-metre crown, four years after being denied gold by Russian dope cheat Mariya Savinova.

The 25-year-old 2012 silver medallist turned on the gas with 150m to go, crossing the line more than 1.20 seconds clear in one minute, 55.28 seconds at the Olympic Stadium.

Francine Niyonsaba of Burundi took silver in 1:56.49 with Kenya’s Margaret Wambui claiming bronze in 1:56.89.

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“I used to be a sprinter, I ran the 100m, 200m in high school,” Semenya said of her finish.

“It was just a fantastic race. Obviously, there can only be one winner and it turned out good for me. It wasn’t about running fast, it was about running a good race.”

Semenya has been at the centre of a raging controversy in recent years because of her naturally occurring condition, hyperandrogenism, which causes elevated testosterone levels.

Rival runners have said they want authorities to revisit rules that limit the amount of testosterone allowed in competitors.

Partially in response to those rumblings, world athletics chiefs implemented restrictions on testosterone levels in 2011.