By Tim Vickery

In South America, the Olympic football tournament is taken very seriously, which is hardly surprising given its historical importance.

A case can certainly be made for the argument that the modern game began at the 1924 Paris Olympics.

Cameroon are the defending champions after beating Spain in Sydney

Uruguay turned up as complete unknowns and astonished everyone by winning the gold medal with a new style of football, full of balletic twists and feints.

Their success, repeated in Amsterdam four years later, had two important consequences.

First, it meant that English football, with its muscular straight-line running, ceased to be the sole reference on how the game should be played.

Second, it sparked off a fever for football that led to Uruguay organising - and winning - the first World Cup in 1930.

The success of this tiny South American country sped up the process of football becoming the truly global game.

Watching the tournament will be a strain for Brazil - Olympic gold is the only title they have never claimed

The subsequent growth of the World Cup means that these days the Olympic title is no longer anything like as important as it was.

But it has its value aside from the historical prestige.

It is also an excellent halfway house between Under-20 and senior football as squads are made of Under-23 players, bolstered by three veterans.

The players in action in Greece this month will also be grateful for the major tournament experience they pick up as many of them will be in Germany for the 2006 World Cup.

Argentina's Olympic squad contains the bulk of the players who played such entertaining football in last month's Copa America.

It was a tournament that was snatched away from them in the final by Brazil, meaning that Argentina have not won a senior title for 11 years.

A gold medal would take some of the pressure off coach Marcelo Bielsa and allow them to prepare for the World Cup in a less hostile atmosphere.

South America's other representatives are Paraguay.

Gamarra hopes to steer Paraguay's youngsters to an Olympic medal

With their senior side showing signs of ageing, Paraguay are looking for their Under-23s to come through and press for a place in the World Cup qualifiers.

The recent run of success began with qualification to the 1992 Olympics, the first major tournament for defender Carlos Gamarra.

He has since gone on to become Paraguay's most-capped player and will be in Greece to pass on his experience to younger team-mates.

Brazil will not be there - amazingly eliminated by Paraguay in qualification.

Watching the tournament will be a strain for Brazil. Olympic gold is the only title they have never claimed - the only one they do not currently hold.

At least they will be represented by their women.

Women's football has enormous potential in Brazil but it badly needs a triumph to give it a kick-start.

For this reason Brazil have invested heavily in this tournament, hiring Rene Simoes - legendary for his work with Jamaica - to coach the team.