The Court of Arbitration for Sport in Lausanne, Switzerland has ruled that American cyclist Tyler Hamilton can keep his gold medal from the 2004 Athens Olympics.

The CAS rejected an appeal by the Russian Olympic Committee Tuesday, which asked the court to strip Hamilton of his time-trial gold medal and give it to Russian silver medalist Vyacheslav Ekimov.

Hamilton tested positive in an initial doping test which appeared to indicate he had used a blood transfusion to boost his endurance. But the International Olympic Committee abandoned its probe after Hamilton's "B" sample was accidentally frozen, leaving too few red blood cells to analyze.

Hamilton is currently serving a two-year ban for testing positive for blood doping at the Tour of Spain in September of 2004. The CAS upheld that ban in February.

Some information for this report provided by AP and AFP.