Quite simply the biggest box office attraction in world football. Barcelona and Real Madrid are the two most star-studded football teams on the planet and boast two players widely considered to be the greatest of their generation - and among the best in history. Oh, and the two sides hate each other.

It is a rivalry rooted in Spain's political past, fuelled by deeper cultural tensions and enriched by an ongoing tradition of sporting excellence. At times the sheer level of antipathy between Barca and Real threatens to ruin the spectacle, with cynical challenges, play-acting and pressuring the referee all common features of recent meetings, but the incredible talent available to both clubs almost always shines through in the end.

Each new contest offers its own catalogue of intriguing sub-plots, and this one is no different.

Barcelona sit top of La Liga but Tito Vilanova has yet to prove he can maintain the almost impossibly high standards of play and success achieved under Pep Guardiola. Jose Mourinho, meanwhile, seems to be battling elements of his own club as Real Madrid seek to ensure last season's title triumph does not go down as a mere interlude in an era of Catalan supremacy.

Real sit eight points behind their rivals after an indifferent start to the season, meaning defeat could create a gap which ultimately proves insurmountable even at this early stage. Barca, though, will be looking to silence the doubts over their fragile-looking defence and heap more misery on Mourinho, the man they contemptuously refer to as 'the translator'. Whatever happens, it will be compulsive viewing.