The phrase lavaros la boca is a blunt Spanish expression roughly telling people to watch what they say, which explains why the clip circulates as a reaction rather than a neutral quote. Its published description links it simply to Alex and Barça, and no reliable source artist or recording year is given in the known facts. Online it has settled into football fan sharing, where a short foreign language outburst can travel as a meme even for viewers who only understand the attitude behind the shouting and use it for rivalry jokes.