Today it was revealed that two of the fastest men in the world tested positive for steroids.
A month before the World Championships are due to begin in Moscow American Tyson Gay and Jamaican Asafa Powell confirmed the positive findings.
The pair hold the second and fourth highest times respectively.
The revelations bring to eight the number of top ten male sprinters who have either tested positive for steroids or have been implicated to have taken steroids.
Earlier this month world number one Usain Bolt insisted he was not doping ahead of the Diamond League meeting in Paris.
Take a look at the full list below.