Following the BBC's announcement that it will screen all of its World Cup games online, employers have been warned that the World Cup could cost the British economy almost £4 billion in lost productivity.
That was the warning from employment law experts if businesses fail to implement proper IT policies ahead of this year's tournament.
It comes just days after the BBC announced it would be screening all of its World Cup games on the internet so that office workers can keep in touch with the action live from their desks.
Even before the BBC's announcement, the competition, which kicks off in Munich on June 9, had already been labelled the first broadband World Cup, with more and more websites geared at entertaining and retaining users rather than simply supplying information.
And with most England matches taking place in the evening, football fans are likely to spend much of their working day keeping up to date with team selections, injury scares and other teams' results.
"Absenteeism is unlikely to be as big a problem this year as it was in 2002," said Joe Shelston, an employment law expert with law firm Brabners Chaffe Street.
"But the danger for employers is that they assume that so long as their workers are at their desk, there is no problem.
"With much more entertaining websites and chatrooms than there were four years ago, football fans are going to find themselves spending more and more time online when they should be working.
"Using an average hourly wage of £12.50, even if half of Britain's workers spent one hour a day surfing the Internet during the World Cup, it would cost UK Plc nearly £4 billion in lost time."
But more than simply lost time, workers' Internet use affects employers' IT efficiency as staff download everything from interactive wall-charts to complicated software providing pop-up news alerts.
"Employers need to set out before the competition kicks off exactly what is acceptable behaviour, and what isn't," Mr Shelston added.
To help employers do just that, the conciliation service Acas, a publicly funded body that aims to improve organisations and working life through better employment relations, has taken the step of publishing World Cup guidelines for employers on its website
According to Acas Chief Executive, John Taylor, employers need to take a flexible approach, to avoid discriminatory practices and be aware that the UK is a multinational society, with a range of national games that people want to watch.
"This is so serious a debate that we have had to issue a World Cup 2006 FAQs, covering everything from does my employer have to provide me with access to the games if I am working, to my employee has a pattern of history of taking 'sickies' whenever there is an important game," Taylor said.
Joe Shelston added that even considering the other potential problems during the World Cup Ė rising absenteeism, being accused of excluding non-football fans or non-England fans and issues surrounding national patriotism Ė a zero tolerance policy will not be right for every business.
"While rising absenteeism or lost time might cost your business, some research suggests that productivity actually increases when employers are feeling good about their national team," he said.
"Allowing some Internet use, while clamping down on inappropriate or excessive use, might strike the balance needed to ensure high morale without damaging your business."