Andy Murray's bid to reach the Wimbledon final this afternoon will receive a giant audience - much to the dismay of British bosses.
Record numbers of workers are predicted to call in sick so they can watch the 22-year-old Scot face American Andy Roddick on Centre Court.
Victory will see Murray become the first British man to reach a Wimbledon final in more than 70 years.
But bosses are in for a "black day", employment laywers warn, as Brits are lured to
skive work by soaring temperatures and the tennis.
End-of-the-week absenteeism, named the "Friday Feeling", could cost businesses around £50m, legal firm Employment Law Advisory Services (Elas) has predicted.
Spokesman Peter Mooney said today is predicted to be the worst ever case.
"We shouldn't underestimate the draw of the heatwave and Andy Murray reaching the semi-finals at Wimbledon," he said.
"Our evidence suggests that more and more workers see the good weather on a Friday afternoon as too good an opportunity to miss, and this combined with the tennis is not good for employers."
British industry's loss is unlikely to be of much concern to Murray though.
He is bidding to emulate the late Henry "Bunny" Austin, whose appearance in the 1938 Wimbledon final was the last by a British man.
To achieve it, he must first defeat Roddick, a former world number one and twice losing-finalist at SW19.
The match pits third-seed Murray, one of the game's finest returners, against its biggest server in the sixth-seed American.
The 26-year-old Nebraskan recorded the fastest serve yet at the Championships - 146mph in 2004 - and has clocked 141mph this time round.
Less power, but no less skill will feature in the first semi-final, where Swiss number two seed Roger Federer takes on German 24th seed Tommy Haas.
Murray's match, dubbed the 'Battle of the Andys' by the British press, will follow the completion of that match.