Embattled Tour de France winner Floyd Landis vowed on U.S. television on Monday (August 7) to clear his name. Samples taken from Landis during July's Tour revealed excessive amounts of the male sex hormone testosterone, so the U.S. rider faces being stripped of victory and receiving a two-year ban; he has already been dismissed by the Phonak team. The U.S. Cycling Federation has referred the case to the United States Anti-Doping Agency (USADA). Landis denied ever using a performance-enhancing drug, telling NBC's 'Today Show' on Monday: "I am saying there is multiple reasons why this could have happened. One of them I will tell you that did not happen was that I added it myself." He originally said that whisky he had the night before the test or perhaps dehydration were possible reasons for the positive result and he acknowledged on Monday that those explanations had caused him problems. Landis's wife Amber, seated alongside him on Monday, was asked if she had looked him in the eye and asked the direct question if he had cheated. She replied: "I don't need to do that. I know what kind of person he is and I know how he thinks. I don't have to ask him that. I believe him 100 percent." Landis insisted that on the Tour he was "clearly the strongest guy there from the beginning". Asked whether he would clear his name and race again, Landis replied: "If I had to choose between the two, clearing my name is the more important one." A second Landis drugs test, or 'B' sample, was revealed on August 5 also to contain an abnormally high level of testosterone, making Landis likely to be the first Tour winner stripped of his title for doping in the 103-year history of the race. Landis had a poor showing on the Tour's 16th stage and was around eight minutes behind the leaders, but he had a remarkable 17th stage to climb back into contention. The International Cycling Union (UCI) must now decide whether to take the title from the 30-year-old Landis and hand it to second-place finisher Oscar Pereiro of Spain. Should Landis get a UCI ban he would then not be able to sign up for a main circuit ProTour team for a further two years. At his age, that would effectively end his career.