A tweet from the account of Mikel Camps, the deputy spokesperson for the Barcelona board of directors, made the astonishing claim, which was subsequently deleted. It was, however, shared by several news outlets - including Spanish publication COPE.
During Real Madrid's 2-1 win against Braga in the Champions League on Tuesday night, the tweet on Camps' Twitter profile read: "It's not racism, he [Vinicius] deserves a slap for being a clown. What do these unnecessary and meaningless stepovers represent in the center of the field?"
Vinicius' Real team-mate Rodrygo issued a stinging response when quizzed on Camps' comments after the game, telling El Chriniguito TV: "I don't know if I can speak, they always encourage us not to speak, but it's pathetic. There's not much to say, very ugly."
The incident comes just days after at least two Sevilla supporters - one a child - were caught on camera making monkey gestures towards Vinicius during Real's 1-1 draw away at Sevilla in La Liga.
The Brazilian attacker has been subjected to several incidents of racist abuse over the past couple of years. Last season he faced monkey chants by Valencia fans, while in May, four people were arrested after an effigy of the player was hung from a bridge.
After the abuse he received in Seville, Vinicius published a statement that read: "The face of today's racist is plastered on websites as on many other occasions. I hope the Spanish authorities do their part and change the legislation once and for all. These people must be criminally punished too."
Real Madrid will travel to Barcelona in La Liga on Saturday for the first Clasico of the season. The Catalan club have yet to respond to the accusations relating to the alleged Twitter post from Camps.