This month's Rugby World Cup is expected to cost UK business millions in lost productivity as staff use corporate systems to keep track of the tournament while in work.
Web content and e-mail security firm Marshal estimates the cost of the tournament to business could by as much as £461m based on the UK's average hourly wage of £14.42 an hour.
As the England team launch their campaign to defend their World Cup title, it is expected that 10% of employed Britons will spend half an hour of each working day watching coverage of matches or browsing the web for updates on scores.
Marshal said productivity will be impacted as employees check the web during working hours for details on matches from live webcasts and audio feeds, pod casts and web logs. IT services will also be compromised as they download videos and interactive scoreboards, eating up valuable bandwidth and opening up the organisation to potential malicious threats.
Michael Clifford, Marshal's VP for EMEA, said, "Employers need to set and enforce policies on acceptable use of the web. Companies can control productivity and bandwidth consumption issues by implementing policies that limit internet access to certain sites to lunch time, and before and after working hours."