As the riders in the European peloton turn their focus away from racing and think about their winter vacations, fired Phonak rider Tyler Hamilton will be eagerly awaiting the outcome of his September appeal to the Court of Arbitration for Sport in Lausanne, Switzerland. If his guilty verdict and subsequent two-year suspension are to be overturned, the sporting world's highest - and final - authority is his last hope.

Anthony Tan spoke to two of the sport's foremost scientific and medical experts to examine the factors that will determine Hamilton's chances in the final hearing at the Court of Arbitration for Sport, now scheduled for January 10, 2006 in Denver, Colorado. Part I below examines the factors in play leading up to the Athens Games, where evidence of blood doping was first found.

Tyler Hamilton was first publicly accused of blood doping during the 2004 Vuelta a España, where it was revealed he failed 'A sample' tests for homologous blood transfusion (mixed cell population) at the Athens Olympics and on September 13 at the Vuelta. However, leaked evidence now reveals suspicions of blood doping dating as far back as April 25, 2004, the day of Liège-Bastogne-Liège. So that is where we will begin.