To the average eye Barcelona's attacking play is a kaleidoscope in which gifted footballers pour into space at whichever angles they fancy. Not quite. Unlike Arsenal, Catalan experts sniff, Barça's flowing forward play is strictly governed by a grid system so that when they lose the ball the whole team is already in position to win it back.
Pep Guardiola, the Barcelona coach, is fond of rhetorical flourishes about the club's duty to entertain, their passion for ingenuity. But in this phase of the club's history - which can trace its origins to the dream team of 1992 - Guardiola has added a dimension that would have been anathema to Johan Cruyff's conjurers. Barça apprentices are taught to see the pitch as a field of eight boxes, all of which must be occupied. Seeing a vacant area, a Barcelona player will slide into the void to restrict the options of the opponent should he find himself in possession.
So graduates of their La Masia academy learn to think two ways at once. Even as they attack, they lay the ground to defend. And from the back, a high percentage of their forward moves start from Víctor Valdés, the goalkeeper, or Gerard Piqué. Sergio Busquets is another starter/stopper.
Barcelona's mystique is not founded, of course, in mathematical calculation. It stems from the sense that the Camp Nou is really an unofficial artistic project.
Through the brilliance of Lionel Messi, Xavi Hernández and Andrés Iniesta, Barça have acquired a global array of diehard followers who reach for the cudgels at the faintest criticism of tiki-taka, or of the practice of rolling around on the ground, clutching one's unhurt face.
This mostly commendable adoration expresses a deep appreciation of football as it should be played, and in this respect Barcelona are hardly slow to promote themselves as guardians of the flame, even while selling their shirt sponsorship to the Qatar Foundation, from a country now embroiled in an alleged Fifa corruption scandal. The "Més que un club" (more than a club) boast is increasingly pervasive.
Yet José Mourinho's nemesis in Spain are ruthless on and off the pitch and are so superior to their contemporaries that their brilliance almost confers an obligation to win the European Cup every year: an expectation that weighs heavily on Guardiola.
Sir Alex Ferguson said: "Guardiola has created a different philosophy for Barcelona. I think the Cruyff era laid the foundation for the width they used in their game and using the full size of the pitch.”
“If you look at their midfield players over the last 20 years, they have all been small. What has changed is the pressing and the areas in which they press the ball. That is what Guardiola has brought to the team," he added. It's all about rondos (piggy in the middle). “Rondo, rondo, rondo. Every single day. It's the best exercise there is. You learn responsibility and not to lose the ball. If you lose the ball, you go in the middle. Pum-pum-pum-pum, always one touch," said Xavi. He makes it sound quite knockabout and easy to replicate. But when the ball is lost for the other 30% of the match "pum" becomes pummel. La Liga fact file