By Mike Verdin BBC News Online business reporter

What's in a kick?

Not just any swipe, that is, but a two-footed lunge which leaves crushed one member of the most lauded set of tootsies in England?

He is a key player, but you could argue the loss of Roy Keane was more significant

Nigel Hawkins, Williams de Broe

It is a question which is absorbing not just the reds - the Manchester United fans - and whites - the ranks of England supporters.

The blues and greys - the besuited league of City workers - are also pondering the implications of the tackle which floored club and country's most celebrated player and squeezed metatarsal into the slim pages of the footballing dictionary.

For Mr Beckham, who faces at least six weeks sidelined, is a match-winner.

And points make prizes not just for trophy cabinets, but coffers too.

Television rights

For Manchester United, the financial threat of Mr Beckham's lay-off looms largest in terms of income from television rights.

Manchester United TV income

2000-2001: �31.2m 1999-2000: �30.5m 1998-1999: �22.5m 1997-1998: �16.2m

"The club has been deprived of a key player at a crucial period in the season," said Nigel Hawkins, analyst at Williams de Broe.

About one quarter of the club's turnover - which totalled �129m last season - is typically attributed to television receipts.

And levels of receipts depend, in the Premiership, on finishing position, with the winner getting some 20% more than the average club, Mr Hawkins said.

In Europe, each stage further Manchester United proceeds earns it about �3m, although much of that disappears in player bonuses, a club spokesman said.

"The club would stand to lose if it did not win the Premiership or proceed any further in Europe," Mr Hawkins said.

"The question is whether you could put that down to the loss of David Beckham."

"He is a key player, but you could argue the loss of Roy Keane was more significant," Mr Hawkins said, referring to the club captain out for the rest of the season with a torn hamstring.

National implications

David Beckham's revenue value at national level is harder to estimate, not least because of the more opaque nature of the Football Association's accounts.

It would be a cruel firm which ditched a star just because he is injured for a few weeks

Andy Korman, image rights expert

According to one report, the FA stands to make more than �100m from World Cup success.

Enough, indeed, to offer a bonus structure which could earn players more than �400,000 each.

"It is very difficult to estimate what the World Cup is worth to the FA," Mr Hawkins said.

"But whatever the FA gains from the tournament, with or without David Beckham, it will not be enough to pay for their plans for a new national stadium."

Pepsi's challenge

But it is not just the clubs and the FA which could suffer.

Leading companies too have attempted to harness Mr Beckham, and his personality, in advertising campaigns.

The player is estimated to have signed contracts with the likes of Adidas, Marks & Spencer and Rage earning him �10m a year.

How will advertisers react?

"It would be a cruel firm which ditched a star just because he is injured for a few weeks," said Andy Korman, a lawyer at Hammond Suddards Edge, and an expert in image rights.

"I have seen conditions applying if someone is out for an extended period - say six months - and so goes out of the limelight.

"But I can't see that happening here. He will continue to be written about.

"You can see The Sun newspaper carrying day by day reports of his metatarsal."

Indeed, the likes of Pepsi have been quick to rally round the fallen idol.

"David has been part of the Pepsi team for many years and we have a long term and personal relationship with him," a statement on Thursday said.

"Therefore, we wish him a quick recovery and continue to support him 100%."

Opportunities?

And, Mr Korman argued, a spell of recuperation could even present fresh advertising opportunities.

"He will have an awful lot extra of free time which he could fill by attending extra off-the-field events, which advertisers might love."

Perhaps healthcare firms might look below the face which sold 1,000 Police sunglasses to toes which could earn them a foothold in a new, soccer-oriented market.

And how long can it be before a photoshoot of Becks in convalescence adorns the pages of Hello magazine?

Entrepreneurs thinking more laterally about the new word on the lips of a footballing nation might like to know that the web address metatarsal.co.uk was still available to buy at 1823 GMT on Thursday.