Divisions play out in Spanish football
It is the most famous institution in Catalonia. Barcelona Football Club, with stars such as Lionel Messi and Luis Suarez, s supported all over the world.
To its local fans, however, it is the embodiment of Catalan nationalism. The Spanish Civil War and the repression of General Franco, when Catalan language and identity were suppressed, copper-fastened this position, and intensified its rivalry with Real Madrid.
The away kit is in the colours of the Catalan flag, and fans join in singing the Catalan anthem before every home match. After 17 minutes and 14 seconds in each match, fans shout "independence" as a reminder of the year when the region was absorbed into Spain.
While Barcelona is renowned around the world and linked with Catalan nationalism, there is a lesser known La Liga team in the city that is associated with a united Spain - Espanyol. As a mark of loyalty, it has a royal crown on its crest.
Traditionally, Espanyol has attracted a fanbase from poorer immigrant workers who came to Barcelona from other parts of Spain. In the past there have been pitched battles between both sets of fans at matches.
Fans of Barcelona may see the Nou Camp stadium as the place to express their national identity, but independence could threaten the club's existence as a global football superpower.
Observers of the sport were left wondering this week whether Barcelona would have to leave the Spanish league if the region becomes a separate state.
They could not possibly attract the same crowds if they were confined to playing local derbies against teams such as Espanyol and Girona. Their occasionally bitter rivalry with Real Madrid is an essential part of their identity.
There has even been speculation that Barcelona could join the English Premier League if Catalonia goes it alone. On Sunday, the Barcelona star Gerard Pique burst into tears as he talked about voting in the referendum.
But despite the high emotion, there were signs of pragmatism from the club's executives.
Last weekend they sought to have their match at the Camp Nou stadium postponed because of the referendum, but they were told that they could have six points deducted if they did not play.
So, they went ahead with the match, but did not allow a crowd into the stadium. Barcelona may have played in an empty stadium as a mark of protest, but in the end football came first.
Independence was one thing, but losing points was a step too far.