Johannesburg - The Confederation of South African Trade Unions (Cosatu) called on bosses on Monday to allow workers to knock off at lunchtime on the day the World Cup kicks off so they can cheer on the national team.
The Cosatu urged employees to let their staff down tools at 13:00 on Friday so they have plenty of time to take their seats as the hosts take on Mexico in the opening match.
"This is a once in a lifetime opportunity and workers should be allowed to be with their families to watch the opening game," Cosatu's Cape Town branch said in a statement.
It said it was "negotiating with employers to close at 13:00". This included the possibility of making up the lost time at a later stage.
The match itself begins in Johannesburg at 16:00, preceded by a lavish opening ceremony with performances by the likes of soul singer R Kelly and the Soweto Gospel Choir.
Labour analysts had already predicted high levels of absenteeism during the month-long tournament, although the influx of tourists should more than offset any damage to the economy.