The chess world is in turmoil after the world champion, Magnus Carlsen, pulled out of a major tournament for the first time in his career with frenzied speculation over whether an opponent cheated.
On Monday, organisers of the $500,000 (£433,000) Sinquefield Cup announced additional anti-cheating precautions, including a 15-minute delay in the broadcast of the moves and increased radio-frequency identification checks. But Carlsen had already withdrawn from the event, announcing it in a tweet with a video of José Mourinho saying: “If I speak I am in big trouble. Big, big trouble.”
