Companies in Birmingham have long been bracing themselves for a surge in absenteeism today when England face Trinidad and Tobago in the World Cup.
Now Birmingham Chamber of Commerce and Industry has tried to quantify how bad it is likely to be.
Firms are expecting a spate of "sickies".
A survey by the lobby group found most (58 per cent) are not making special provision to allow employees to tune into games. Twenty four per cent said they would be and 18 per cent said they would only allow it for matches involving England.
Manufacturers are set to be hardest hit. Forty per cent are expecting an increase in absence compared to those in the service sector (31 per cent). A larger proportion of manufacturers (20 per cent) are also predicting a decrease in turnover compared to their service sector counterparts (15 per cent).
Twenty-nine per cent overall reckon on an increase in absence or sick leave during the tournament, while 12 per cent forecast a decrease in turnover as a result of the football feast.
Eighty-two per cent predict no change in turnover.
James Cooper, policy adviser at BCI, said: "These results suggest that businesses are very relaxed about the effect that the World Cup will have.
"Firms have been lucky this time around in the sense that England's games have fallen largely outside of working hours. Many employees will probably wish to leave early today to see the group game against Trinidad & Tobago, while there is a possibility that England could play a quarter final at 4pm on June 30 if they finish second in their group and win their second round match.
"Disruptions could occur for firms who operate night shifts and to those who usually work outside of traditional office hours, although few of our members have cited this as a problem."
"Roughly half of our members have made some sort of provision to allow employees to stay in touch with matches at work, the other half see little threat to their business as a result of the tournament," said Mr Cooper.