Like a disease the mishap replays over and over again in the player's mind, increasing his anxiety and frustration.
More after the break
Fear replaces confidence, causing a succession of mistakes. Nerves debilitate with the power of kryptonite and self belief does for a football what spinach does for Popeye.
But, how do you restore your powers of confidence after a mistake? Have a policy for dealing with the error and don't react, says former Manchester United and England psychologist Bill Beswick.