Rather than contesting his own doping case, Papp met with USADA officer Travis Tygart in early 2007, and agreed to testify in the USADA arbitration hearing examining Floyd Landis' positive result for testosterone at the 2006 Tour de France. He also revealed the identity of two corrupt American doctors who had prescribed him banned drugs. At the Landis hearing, Papp described how synthetic testosterone gel helped him to recover during multi-day stage races. USADA used this testimony to refute earlier claims by Landis' attorneys that testosterone could not help Landis win the 2006 Tour, and that he would be unlikely to use it if he knew the substance was detectable by testing. Papp rebutted both of these claims, saying it was easy to stay below the threshold of a positive test, and that the gel helped him greatly in recovering between stages.