The time spent by UK workers following the World Cup on the internet could cost employers almost £4bn if they do not put procedures in place to curb abuse, according to research.
Last week, the BBC announced it would be screening all of its World Cup games online 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 9 June, 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," he added.
Using an average hourly wage of £12.50, even if half of the UK's workers spent one hour a day surfing the internet during the World Cup, it would cost employers nearly £4bn in lost time
"Employers need to set out before the competition kicks off exactly what is acceptable behaviour, and what isn't," Shelston said. "This could be done simply by circulating a reminder outlining what is acceptable, or drawing workers' attention to your existing IT policy.
"Most importantly, employers must be consistent. There's no point in managers disciplining staff for keeping an eye on the World Cup, then tuning in around the clock themselves during the next test match."
But that is not to say there is no room for flexibility, Shelston said. Even considering the other potential problems during the World Cup – rising absenteeism, being accused of excluding non-football fans or non-England fans and issues surrounding national patriotism – a zero tolerance policy will not be right for every business, he explained.
"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."