The pair had asked the Court of Arbitration for Sport (CAS) to reduce their bans to three months.

Former 100 metres world record holder Powell and Simpson, who won 4x100m relay silver at the London 2012 Olympics, both tested positive for the banned stimulant oxilofrine at last year's Jamaican national championships.

Giving its ruling, the CAS said: "They put forward that the offence committed was minor because it was caused by contamination of the food supplement Epiphany D1 by the banned substance oxilofrine and requested that the suspensions be reduced to three months."

Powell took to Twitter to express his relief at the ruling.

"Thank u [sic] to The Court of Arbitration for Sport.

"Finally this weight has been lifted off my shoulders.

"Justice has been served.

"Now let's run!"

Sherone Simpson, along with Asafa Powell, is now free to race competitively again ©AFP/Getty Images



Simpson said "I feel total relief and that we have finally been vindicated.

"We both knew that we had done all we could to ensure the supplement was ok before taking it...our actions were not intentional and CAS has recognised that.

"I am truly thankful."

Last month, it was reported by the Jamaican Observer that Powell and Simpsons' ban would be cut to 11 months after an agreement by the International Association of Athletics Federations and the World Anti-Doping Agency.