Argentinian primera división (top division) football is full of historical rivalries that are both notorious and colourful. This footballing folklore more often than not manifests itself in cheeky banter between opposing sets of fans. At times it famously descends into wanton violence. Teams define themselves by who they despise. Chants that can be heard in stadia every weekend are full of such insulting language about opponents that uttering such things publicly in most countries would get you arrested.