Boris Onishenko's rigged Ã©pÃ©e
In 1976, scandal hit the modern penthathlon in a bizarre manner that seemed more like something from a spy film than a sporting contest. In the fencing discipline of the pentathlon, the USSR's Boris Onishenko - a major in the Red Army and one of the world's finest penathletes - seemed to be winning his contests incredibly easily. When officials tried to examine the Ã©pÃ©e he was fighting with, the Soviets desperately tried to stop them getting hold of the weapon.
When officials did manage to get their hands on the blade, the reason for this became apparent. Somehow, despite regular checks, the Soviets had managed to rig the complex system of electronics required to register a hit, and had inserted a button that allowed Onishenko to register winning hits at will. The Soviet team was banned from the competition, and Onishenko ended a glorious career by vanishing back to the USSR, where he lived in relative obscurity.