Alberto Contador has received a backdated two-year ban from the Court of Arbitration for Sport and stripped of his 2010 Tour de France title.
A decision on the long-running case, which centred on the Spaniard's positive test for clenbuterol during the 2010 Tour, was finally announced on Monday.
The suspension means Contador loses his third Tour title as well as all of his results from 2011, including his victory in the Giro d'Italia.
As the ban is back-dated, the time since the positive test counts as time served and Contador will be able to return to racing on August 6 2012. He will not be able to participate in this year's Tour de France.
Contador had been cleared by the Spanish cycling federation, which accepted his claims that he ingested the banned substance by eating tainted meat.
But the World Anti-Doping Agency and the International Cycling Union (UCI) appealed that verdict to the highest court in sport, where his explanation was not accepted.
The CAS stated that both the meat contamination theory and WADA's theory, which suggested the substance entered Contador's system via a blood transfusion, were "equally unlikely".
Instead the CAS panel decided that the "ingestion of a contaminated food supplement" was a more likely cause, but Contador's explanation failed to meet any criteria that would reduce the period of ineligibility.
Andy Schleck is now set to inherit the 2010 Tour title after Contador became the second Tour champion in history to be disqualified due to a doping violation.
UCI president Pat McQuaid did not welcome news of the ban, instead reflecting on how damaging the case has been for the sport of cycling.
"This is a sad day for our sport. Some may think of it as a victory, but that is not at all the case," he said.
"There are no winners when it comes to the issue of doping: every case, irrespective of its characteristics, is always a case too many."
Spanish cycling federation president Juan Carlos Castano added: "We are obliged to comply with (the decision) but we don't agree with it. It's very bad news for Spanish sport. For us this journey has ended."
The CAS also revealed that the UCI have requested a fine of almost 2.5 million euros for Contador, a case that will be heard at a later date.
Did Alberto Contador deserve to be given a two-year ban?