Andres Escobar
Many people on this list paid a hefty price for their career-defining mistakes. But nobody suffered a cost as high as Escobar after he scored an own goal against the U.S. in the World Cup. It was an unfortunate moment and a low point for the Colombian international.

Then he went home after the tournament to visit his family. But a gunman confronted him outside a bar and murdered him in a brutal fashion. Allegedly he referred to Escobar’s mistake and slayed him for it. Escobar had no relation to the infamous drug lord of the same name (via The Sun).