Was it a goal, or wasn't it? The question shouldn't need to be debated in the next five weeks in Brazil, where goal-line technology will be used for the first time in a World Cup.
Fourteen cameras, seven trained on each goalmouth, have been hung up in all 12 World Cup stadiums. The cameras will record 500 images per second, and a computer will digest the frames. Within a second of a ball crossing the line, the referee's special watch will vibrate and flash "GOAL."
End of the debate? It should be. The designer of the system says 2,400 tests have been run in Brazil, without a mistake.
"This is the future," said Dirk Broichhausen, who heads the German company GoalControl, whose system will be used at the tournament and was demonstrated Monday at Rio's Maracana stadium.
It's also a type of technology that FIFA repeatedly balked at in the past. But the 2010 World Cup changed that when a shot by England's Frank Lampard in the second round against Germany was clearly over the line, but disallowed.
That goal would have tied it 2-2. Instead Germany won 4-1. And that helped end the indecision.
"Most of the time the referee doesn't have the best vantage point for his decision, goal or no goal," said Johannes Holzmuller, who heads a FIFA program that helped implement the technology. "The same applies for normal TV cameras."
He said the human eye could record only 16 "frames" per second, no match for a high-speed camera.
