These were the Hellanodikai (literary meaning "the judges of the Greeks").
Initially, the post of a Hellanodikes was hereditary.
After
It was their responsibility to award the prizes to the victors, or to punish and impose fines on those who did not obey the rules. In order to promote the Games and assure a perfect final spectacle, they had to supervise the athletes during the training month prior to the Games, select those with satisfactory training and single out others of poor performance. Their judgment was covering not only the area of physical performance, but was extending over the athletes' overall character and morality.