 Michels was one of 19 positive tests at the 1983 Pan American Games in Caracas, where new sophisticated testing procedures were introduced for the first time, in earnest.Michels repudiated his positive test for synthetic testosterone, which before the introduction of the Gas Chromatography-Mass Spectrometry assay, could not be identified in athletes' samples.Curiously, Michels was cleared to compete in the Games after testing clean as part of a pre-screening program conducted by the USOC.