Four men detained in Spain earlier this week over a suspected hate crime in the hanging of a black effigy of Brazilian football star Vinicius Jr from a bridge have been released on bail, a Madrid court said on Thursday.

The men, who are also being investigated for an offence against Vinicius' moral integrity, have been banned from approaching and communicating with the Real Madrid winger pending further investigation.

The inquiry was opened after an inflatable black effigy dressed in the No. 20 jersey of Vinicius Jr was hung from a bridge in front of Real Madrid's training grounds before a match against Atletico Madrid in January.

La Liga president Javier Tebas apologised for his online rant at Vinicius.

"Well, it seems that the result has not been very good, right?," Tebas said.

"I mean, to all those who have understood that this was an error due to the form, due to the time... I have to apologise," he said.

"I apologise to Vinicius and to anyone that understood that I was attacking Vinicius."

Tebas said he shared the 22-year-old's frustration over the lack of action to eradicate racism in Spain, and took aim at football organisers and Spanish authorities.