The Brazil defender was abused with vile songs and sounds after the Madrid derby on Wednesday night, despite the presence of his son at the Santiago Bernabeu
The Brazil left-back didn't feature in Madrid's 3-0 win, but was abused during the warm-down by the visiting supporters left in the ground after the game as chants of 'Marcelo, eres un mono' (Marcelo, you're a monkey) rang around the near-empty stadium.
The presence of a young boy, thought to be the player's son, not only failed to deter the abusers but merely made things worse as some Atleti fans chanted 'Marcelo's not your father' and 'We hope your father dies'.
Both clubs are yet to comment on the chanting, but such scenes are all too common in stadiums across Spain, which has a long list of notorious incidents.
Back in 2004, Samuel Eto'o threatened to walk off the pitch following racial abuse at Zaragoza, while more recently Marcelo, Dani Alves and a host of other players have been subjected to monkey chants in away games - particularly in derby clashes.