Computer chips replace football's guessing game
The system is called 'Goal Line Technology' – or GLT.
A computer chip built into the ball senses the strength of magnetic fields produced by cables behind the goalposts and under the pitch. If it crosses the line, the chip relays a message to a special watch worn by the referee, both assistant referees and the 4th official.
The system is a joint creation by Cairos Technologies working with sports manufacturer Adidas. The two have been working on it since 2003.
It was first put into action in the semi-finals of the Club World Cup in Japan on Thursday night.
Should it be successful in testing, the GLT looks set to revolutionize how decisions are made in football.