Disgraced former world 400m champion Jerome Young has been told he must hand back the Olympic relay gold medal he won in Sydney in 2000.
Young was subsequently revealed to have failed a drugs test prior to the Games, and has since been banned for life after a second positive dope test.
Earlier this year, Young insisted he was going to keep his gold.
But now the International Olympic Committee have told him that he must return it immediately.
In July, Young said: "I was their scapegoat - I am not going to give up a medal for something I did not do."
The Court of Arbitration for Sport (CAS) upheld an appeal by US athletics officials this summer that the rest of the squad - including five-times Olympic champion Michael Johnson - keep their gold medalS from the event.
Athletics' ruling body, the IAAF, had recommended to the IOC that the American squad be stripped of their medals
Young competed in Sydney without the world knowing about his positive 1999 test, because the American authorities had chosen not to take any action against him.
It was only three years later that the test result came to public prominence.
The IOC ruled that his results for the two years after the positive test - including Sydney - be annulled.