The Danone Nations Cup has been around since 2000 and is the world's biggest football tournament for children aged 10-12.
The competition was conceived after the 1998 World Cup in France, in response to a growing international interest in football.
FIFA now endorse the tournament and Zinedine Zidane is recognised as one of its main ambassadors.
There are local, regional and national rounds of qualifiers before the winners (boys and girls) fly to wherever the finals are being held that year.
This year, the finals were held at the RCDE Stadium in Barcelona, home to Espanyol.
Barcelona's under-12 side had been through the qualification stages and were due to play in the finals.
In the previous rounds, Barça's team were allowed to wear the club's colours, but in the final round of games they would have to wear the red of Spain.
Being a proud Catalan club, Barcelona were unwilling to allow their players to wear the Spanish colours, according to Cadena Ser's Catalan radio programme Què T'hi Jugues.
After Barça's refusal to play, Villareal took their place and played in the red kit.
The fact that the finals were held in Catalonia made for even more political tension, bearing in mind the strikes and protests about Catalan independence.
Even Pep Guardiola has weighed into the debate, saying that the arrest of Catalan leaders was "an attack on human rights".
"Spain lives in an authoritarian drift in which anti-terrorism laws are used to prosecute dissent," he said in a press release.
"This fight won't stop until the repression stops and we find a peaceful and democratic solution."
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