They arrive with hubristic anticipation, ridiculously over-hyped by the public and convinced of the superiority of their players.

The manager's every decision is scrutinised, while the tabloids work the country into a jingoistic frenzy. Yet it always ends in familiar tragedy. A penalty miss, harshly disallowed goal: doesn't matter. The same purgative national introspection will follow. England complain of 40 years of hurt? Try 80.

It is one of the enigmas of international football. Despite the excellence associated with Spain's club game, the hallmark of the national team has been profound underachievement. Since their first professional match in 1926, they have won the 1964 European Nations Cup . . . on home soil in a then much-reduced competition . . . and reached the final of the same tournament 20 years later. And that's it. Their fourth place in the 1950 World Cup belies the fact they finished bottom of that campaign's deciding league stage, a campaign that included a 6-1 humiliation by Brazil.

Of the world's great leagues, Spain is the only one not to provide a World Cup winner.

Indeed, they've never even reached the semi-finals.

The Spanish themselves call it the curse of the quarterfinals. If only that were so.

For while they have been eliminated at that stage five times in tournaments over the last 20 years, it doesn't explain the traumatic first-round exits of France '98 or Euro 2004. Such a blinkered explanation seems typical of the country's psyche. Overtly confident, the blame is always placed elsewhere: a referee's error, a nefarious conspiracy or, more simply, rank bad luck.

Yet 'the curse'' also speaks of an underlying inferiority complex: that la seleccion is afflicted by some inherent mental block when it comes to the crunch. It's a mindset so embedded, that it's the central theme in the country's greatest work of literature, Cervantes' Don Quixote.

But what lies behind that psychological inhibition?

Here, of course, one of the most common explanations given is the country's fractured political make-up. That the separatist ambitions of the Basque and Catalan players cause disruption when they appear for the national team. Indeed, if you walk into a bar in Barcelona or Bilbao over the next few weeks you'll see more Ukrainian and Tunisian flags than Spanish ones. Curiously however, it's something the Spanish themselves don't mention when it comes to the players. For Juan Ignacio Gallardo, who covers the national team for the Madrid sports daily Marca, it isn't even an issue.

"I don't think it influences the players, " he says. "Carlos Puyol, the Basques, the Catalans, they are all professionals, so whenever they play they give 100 per cent. Sure, some players feel more pride in the national jersey, such as Raul or Sergio Ramos. But remember, they are not forced to play for la seleccion. In recent years, a Galician, Nacho, refused and Oleguer, the Barcelona defender, decided he wouldn't play because he is a firm believer in Catalan independence. Luis [Aragones] rang him and he refused. I'm not sure it's a factor for Spain's lack of success."

The point about national pride is an important one however. There is the belief that some regionalist players only turn out for Spain because the national team's dependence on them reinforces claims for self-determination. That while Spain can't function without them, they are well capable on their own. Indeed, in USA '94 as much as two thirds of the squad came from either the Basque country or Catalonia. And some vociferous separatists have featured. Josep Guardiola, for example, captained the side while at the same time lobbying for Fifa to sanction a Catalan national team. When Chelsea's Basque left-back Asier del Horno was called up for the first time meanwhile, he was concerned about being photographed next to the national flag. Just as well the Spanish anthem has no words. But since international football so often comes down to pride and communal emotion, though the players are professionals, the question remains about how truly deep-rooted their commitment is as a result.

When it comes down to it, the well of patriotism that can so often carry a country over . . . the Spanish marvelled at the spirit of the Irish in the dying minutes in Suwon . . . is essentially missing for many of them. Like the public, it is something players such as Guardiola don't like to talk about when explaining away another failed campaign.

One thing they do like to talk about, though, is conspiracies. At this, they are almost as accomplished as the Italians. Too many key decisions in too many big games have gone against them they claim. Three in particular stand out. In the USA, when Mauro Tassotti's elbow smashed Luis Enrique's nose in the penalty area just before Roberto Baggio's late, late goal put Italy into the semifinals. In Euro '96 when Javier Manjarin and Julio Salinas had two legitimate goals ruled out before the hosts England defeated them on penalties.

And, most notorious of all, against the hosts again six years later when they joined the Italians in bemoaning the suspicious linesman's rulings awarded to Korea. Conspiracies are a push from a country where Real Madrid are alleged to have benefited from the same process, but Spain have certainly been afflicted by dreadful luck.

The riposte to that, of course, is that players of genuine quality make their own luck. And underneath it all, that may be the real reason for Spain's successive failures. While they have always had good, technically sufficient footballers, they have never been blessed with international class of the highest level.

As Phil Ball argues in his seminal book on the Spanish league, Morbo, it speaks volumes that only one Spaniard, Luis Suarez, has won the European player of the year, in 1960, while their most celebrated internationals are two naturalised foreigners . . .

Alfredo Di Stefano and Ladislao Kubala.

Indeed, from arguably their finest campaign, Euro '84, few players other than perhaps goalkeeper Luis Arconada or Rafael Gordillo, remain in the memory. That 1994 quarter-final against Italy is a perfect example. Whereas Baggio took his one-on-one chance to win the game, Spanish striker Julio Salinas squandered an identical opportunity moments beforehand. Similarly, at the same stage in Euro 2000 against France, while Zinedine Zidane assumed the responsibility expected of him and converted a decisive freekick, Raul buckled and missed a stoppage-time penalty.

Which brings us to the current squad. For Spain, genuinely, have their finest in decades. A truly talented and now mature goalkeeper in Iker Casillas, a strong central defence in Carles Puyol and Pablo Ibanez, an embarrassment of options in midfield . . . from Xavi and Iniesta to Alonso and Cesc Fabregas . . .

and, for once, a bona fide goalscorer in David Villa.

As manager Aragones stated last week, "I have 23 good reasons to believe in this team. We've got to banish the excuse mentality. I've never liked alibis that don't justify anything."

And yet he may be creating one for himself. Despite the team's form through the winter, and personnel seemingly ideally suited to 4-4-2, he is determined to build the team around Raul, who hasn't looked fit since returning from a tear to his cruciate ligament in February. Last week's experiment with 4-33 in a scoreless draw against Russia failed, and Aragones is now in a race before Wednesday week's game against Ukraine to find a system that works for a player who hasn't been in form for two years and has yet to truly succeed for the national team.

Of course, even if he does, and Spain finally live up to expectation, their likely path will see them meet Brazil. In the quarter-finals.

The curse once more. And the same ordeal all over again.