At the 2004 Summer Olympics in Athens, Hamilton won the gold medal in the men's individual time trial. That medal was placed in doubt on September 20, 2004, after it was revealed that he had failed a test for blood doping (receiving blood transfusions to boost performance) at the Olympics. Two days after the announcement of his positive test result at Athens, the IOC announced that Hamilton would keep his gold medal because results could not be obtained from the second, backup sample. The Athens lab had frozen the backup sample, which made it impossible to repeat the blood doping test.[3] The Russian Olympic Committee filed an appeal with the International Court of Arbitration for Sport seeking to strip Hamilton of his gold medal and grant it to Russian silver medalist Viatcheslav Ekimov. However, on June 27, 2006, the Court rejected the Russian Olympic Committee's request to strip Hamilton of his gold medal.[4]

At the time the IOC announced that he would retain his gold medal, Hamilton had just withdrawn from the Vuelta a España. He won the stage 8 individual time trial on September 11, 2004, but resigned from the race six days later, citing stomach issues. Being the winner of the stage, he was subjected to anti-doping tests, and was informed by the Union Cycliste Internationale (UCI) on September 13, 2004 that his two test samples from 2 days earlier had showed the presence of a "foreign blood population."[5] After initially supporting Hamilton, his Phonak team managers withdrew their support after a second member of the team, Santiago Pérez, was found positive for the same offense at the 2004 Vuelta a España.[6]

The positive sample at the Olympics, and the positive test at the Vuelta were not the only indications that Hamilton was manipulating his hematocrit level. In April 2004 his health test blood samples were found to have a very high ratio of hemoglobin to reticulocytes (young red blood cells), which is indicative of EPO use or blood doping. His score for the test was 132.9, where a typical clean athlete would score 90, and where the UCI mandates removal of the athlete from competition if the score exceeds 133. This sample also showed clear evidence of a mixed cell population (i.e. someone else's blood was in his bloodstream). However, neither of these pieces of evidence in isolation constituted a positive drug test (and the test for a mixed cell population had not yet been officially adopted), so no formal action was taken.[2]

Given the short interval (two weeks) between the Olympics and the Vuelta, it is very likely that the positive test for blood doping in the Vuelta was for the same blood doping event which had been detected at the Olympics (because the foreign blood cells used in homologous blood doping would remain present in the athlete's body for a period of months), confirming the accuracy of the positive test at the Olympics. It seems clear that Hamilton had in fact blood doped before the Olympics, but had retained the gold medal on a technicality.[2]

On April 18, 2005 Hamilton was sentenced by the United States Anti-Doping Agency to a two-year suspension from professional cycling,[7] the maximum sentence for a first-time offense.

On May 18, 2005, he appealed the ruling to the Court of Arbitration for Sport but, after an adjournment to allow Hamilton to gather additional evidence, the Court dismissed his appeal.[8] Hamilton’s defense claimed that the UCI-sanctioned test was insufficiently validated (and may therefore have returned a false positive result) and that some of the agencies involved had concealed documents that would have supported his case. He also maintained that, even if a foreign population of cells was present in his blood, the cells were naturally present and not the result of a transfusion. Hamilton's lawyers at the time offered the explanation that he might be a Chimera, something Hamilton later disavowed.[1]

Hamilton was banned from competition until September 22, 2006, two years from the date his "B" sample taken in the Vuelta a España was found to be positive. Although current UCI ProTour rules would have effectively doubled the period of his suspension (until September 22, 2008), his positive test occurred before those rules were put into effect in 2005.

willi wrote:
But can I ask for some Screenshots of the best riders on the best teams?

Tommeke wrote:
i meant there are some riders double