Such is the extent of the rivalry between Real Madrid and Barcelona it even reaches social media, where the two clubs have been battling to become the first with 100m Facebook page likes.
Los Blancos emerged victorious, reaching the milestone on Saturday night. Barcelona didn't let them win easily, though, as they opted to attempt to encourage fans into liking their page.
According to Marca, the Blaugrana sent out private messages to fans imploring them to help the club reach 100m first. It ultimately failed, however, as Barcelona were left languishing on just 99.8m.
MARCA: Barca were sending pvt msgs to followers to beat Real Madrid with more Facebook likes but they managed 99.8 millon & couldn't.
— M•A•J (@UltraSuristic_) April 2, 2017
Still, that total is not to be scoffed at, especially when considering the number of likes of some of Europe's other big clubs. Manchester United, for example, have 73m, while Premier League leaders Chelsea have 47m.
Jose Angel Sanchez, Barcelona's general director, has spoken of his satisfaction with the club's position on Facebook.
"We will work to keep consolidating our leadership in the social media sphere," he said. "We have a fantastic relationship with Facebook and its strategic direction is helping us build a powerful and committed audience."
Both Barcelona and Real Madrid are in action on Sunday as they look to assert their authority where it really matters.