In his post, Stoichkov included a photo of Lamine Yamal, a Barcelona player who celebrates his goals by writing the number 304 with his hands. Stoichkov added a caption to the photo, listing the number of Barcelona titles and Clasicos won by the team, while also noting that Real Madrid has no titles in that time frame.
The number 304 is significant because it is the postal code of Yamal's neighborhood in Mataro, Spain. Stoichkov's post was likely intended to tease Real Madrid fans and supporters.