The defender had wrestled forward Vinicius, to the ground and the pair began to tussle. As Vinicius attempted to sit up and escape the clutches of his marker, Tachi lent in and bit the Real star on the back of the head.
Vinicius and his Real team-mates were furious at the shocking attack, which took place right in front of the referee who was just inches from the incident.
A scuffle broke out between both sides, with Vinicius having to be dragged away from his opponent as he showed his fury at being bitten.
When tempers were calmed, the ref unbelievably only showed him a yellow card and then booked Vinicius who had been the victim of the horrible assault.
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One thing is sure, Vinicius Jr. won’t forget his first experience of the Madrid derby.