Sport is no stranger to scandal, but several recent fixtures have put governing bodies in the spotlight, says Max Duthie

In their 2005 book Freakonomics, economists Steven D Levitt and Stephen J Dubner argued that sumo wrestling, that most noble and ancient Japanese sport, was riddled with corruption.

They analysed data from 32,000 bouts over 11 years and controversially concluded that a significant number of those bouts had been rigged, with one wrestler having agreed to 'tank' or take a dive to let his opponent win (in return for a reciprocal gesture at their next meeting).