Jude Bellingham voiced his anger towards the referee after Real Madrid were beaten 2-1 by Atletico Madrid in the derby.
According to Fabrizio Romano on social media, the England midfielder shouted “Two red cards! Two!” towards the official after the final whistle.
Real Madrid played almost the entire second half with 10 men after defender Dean Huijsen was sent off.
The defeat leaves Jose Mourinho’s side fourth in the La Liga table on 15 points. Real Madrid are now six points behind leaders Barcelona.