Elaine Thompson was very surprised by her triumph in the women's 200 metres at Rio 2016 after battling a hamstring injury.
The Jamaican held off world champion Dafne Schippers on the home straight to seal a sprint double on Wednesday, having won the 100m four days earlier, edging the Dutch athlete by a tenth of a second as she prevailed in a time of 21.78 seconds.
Thompson becomes the first woman to win gold in the 100 and 200 at the same Games since Florence Griffith Joyner in 1988.
She is the seventh woman to have done the sprint double and said: "My school motto was 'let the light shine' and I let my light shine tonight.
"It's a big surprise to me because I have had a hamstring injury. You must overcome these things and tonight I am standing here with a gold.
"To beat Dafne is a hard run."
Thompson will attempt to win her third gold of the Games in the 4x100m relay.