Cristiano Ronaldo scored a penalty that made the score 4-1, and his exuberant celebrations angered many 'Rojiblancos'.
While passing the centre circle on his way back to his own half, Varane then kicked the ball towards the Atlético bench, and at this point Simeone's anger boiled over.
Simeone was eventually sent off as tempers exploded.
"Varane provoked me by kicking the ball at me. Us older guys don't like people doing that kind of thing to us," he said afterwards.
El Cholo did want to apologise, however: "I also made a mistake with my reaction. He's a young guy with a bright future."
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