Four men detained on suspicion of hanging an effigy of Real Madrid star Vinicius Junior from a bridge have been banned from Spanish stadiums, a Madrid court ruled Thursday.

The men, who were detained Tuesday, were released on bail and banned from coming within 1,000 metres of a La Liga stadium during matches.

The dark-skinned inflatable dummy was hung by the neck from a bridge near Real Madrid's training ground several hours before a derby clash with Atletico Madrid on January 26.

Above it was a 16-metre banner reading 'Madrid hates Real', police said.

The four men are being investigated for a hate crime.

Police said three of them were members of "a radical group of fans of a Madrid club" who were previously flagged during matches as "high risk".

Their arrest came two days after racist chants were hurled at Vinicius during Real Madrid's 1-0 defeat at Valencia, sparking an international outcry.

The 22-year-old Brazilian international has faced racial abuse since he joined Real in 2018 and the latest incident has kicked up a storm over whether Spain is doing enough to stamp out racism in football.

Police on Tuesday arrested three youths in Valencia for "insults and gestures with racist overtones" towards the player during Sunday's match that amounted to "an alleged hate crime".