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It took just nine minutes for Liverpool to shoot ahead of rivals Chelsea in their showdown in November. Emre Can, the German midfielder, put Liverpool in front at Anfield, their home stadium, with a deflected goal that threatened to put Chelsea’s then unbroken run of wins in jeopardy.
Five minutes later, the blues equalised with the help of the Premier League’s goal detection system, designed to show with 100 per cent accuracy whether or not the ball has crossed the goalline.
Liverpool keeper Simon Mignolet stopped Chelsea captain John Terry’s header, but had to scramble to try and stop Gary Cahill’s rebound from edging over the line.
An array of cameras, monitoring the goalmouth from various angles high up in the stadium, helped make the decisive call. As Mignolet held the ball in his arms, the system, provided by UK company Hawk-Eye, owned by Sony, detected that the ball had crossed the line. An alert sent to the referee’s watch reported the simple outcome: goal.
Goal line technology was embraced by the Premier League last season, after Fifa, the game’s world governing body, finally acceded to pressure for a more accurate system of determining goals.
Controversy about the absence of a definitive way of deciding goals was sparked in the 2010 World Cup, when England captain Frank Lampard was denied a crucial goal against Germany. Replays suggested that the ball had in fact crossed the line after hitting the bar, but instead of drawing level at 2-2, England went on to lose the match 4-1. Fifa president Sepp Blatter later apologised.
Since then the costly technology has been installed in all 20 Premier League stadiums at a cost of £250,000 per venue. There have been 31 “key incidents”, where a definite goal decision would have been impossible without goal line technology.
Germany’s top flight league is set to follow suit from its 2015-16 season, after clubs voted for the introduction of the technology. Italy’s Serie A league will also start using goal line technology next season.
Although costs have fallen, it is still beyond the reach of less well-funded, lower-league football. In 2013, England’s second-tier league considered using the technology, but the cost was “considered to be prohibitive”, says a representative.
But even as goal line technology has won a long battle to become accepted in mainstream football, other sports are moving more quickly into a new world of immersive data and video. Other sports have been quicker to adopt on-pitch cameras for some uses, for example Rugby Union began testing referee cameras in 2013.
Spanish company First V1sion is developing cameras that are embedded into jerseys, allowing for player vision of the action to be broadcast simultaneously. The technology has been trialled in European basketball, with the referees for Real Madrid and Barcelona’s clash in February broadcasting the match live from their jerseys.
In the US, American Football stars have their every step scrutinised. Tracking chips in their shoulder pads record their movements, helping to create a rich set of data that shows how fast players run, over what distance and how quickly they accelerated.
The technology has been deployed to half of the NFL’s stadiums, giving broadcasters and fans live data on the runs that players have made. To avoid giving teams an unfair advantage, the raw data are currently withheld from clubs until the entire league is set up with the system, which uses radio frequency ID (RFID) chips.
Ian Pearson, a technology consultant and self-described futurist, believes that the data collection will not stop at movements. He envisages monitoring statistics such as hydration, sweat, blood pressure and sugar levels.
“You could get an unbelievable amount of data from every player throughout the game,” says Mr Pearson. His Future of Football report with HTC, a mobile phone company, last year went even further, describing a game where players wear contact lenses that allow augmented reality displayers, and drones buzz above the field, broadcasting footage.
But the pace of change is likely to be slow. Any innovations in the game of soccer require the approval of Fifa’s International Football Association Board, which is known for its cautious approach. In February, it delayed the introduction of video replays for fouls by at least a year.
Blood, sweat and tears monitors may be some way off yet.
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