Last Wednesday night, long after the final whistle had been blown on a riveting Libertadores semi-final, a little corner of Palmeiras’ Allianz Parque stadium was still bouncing. Bathed in a sea of blue and yellow, it looked like a barrio of Buenos Aires had been transported to São Paulo. The travelling fans’ excitement was understandable. Boca Juniors had just made it to the final of the Copa Libertadores, South America’s Champions League, where they will take on city rivals and eternal enemy River Plate. Shortly after the game, a Brazilian colleague – despite the disappointment of seeing both his country’s remaining representatives dumped out on consecutive evenings by the two Argentine giants – turned to a friend and said, “This is going to be the biggest final in sporting history.” Although that might sound like an exaggeration, he’s not far away from the truth. In club football, there has perhaps never been a game that means so much to so many. Boca Juniors versus River Plate often tops lists of the most intense derbies in world football, and for good reason. The rivalry between these two – the Superclásico, as it is known in Argentina – runs deeper than just the beautiful game. Having both emerged in the working-class port neighbourhood of La Boca, River Plate then decided to move to the affluent Nuñéz suburb in the north of the city in 1925, marking themselves out as the club of high society. Just a few years later, after their wealth had brought a series of titles and expensive signings, River were christened Los Millionarios – The Millionaires – a nickname they have carried ever since. Boca, meanwhile, are known as ‘the people’s club’. While that class division between the clubs and their respective fans is no longer as clear-cut as it once was, the enmity remains just as powerful.