As chief executive of the U.S. Anti-Doping Agency, Tygart's mission is to make sports a sanctuary for finding out who's most talented and who worked the hardest, not who's the best cheater.
Most recently, that mission has led Tygart to spearhead the case that's ended Armstrong's cycling and triathlon careers. It was a task that once seemed impossible.
Now, in the wake of a scathing report that detailed an alleged doping system run by Armstrong's teams, the cyclist has been cut loose by his major sponsors and is no longer the face of the Livestrong charity he founded.
(Copyright 2012 by The Associated Press. All Rights Reserved.)