Samuel Eto'o risks a long ban after the Inter striker was caught on camera head-butting Cesar in a Zinedine Zidane-Marco Materazzi style.
The off the ball incident occurred 38 minutes into today's Serie A match against Chievo.
The two players had argued a few moments earlier and Eto'o opted to take 'revenge' by running towards him to head-butt Cesar in the chest.
The referee, assistants and fourth official at the Stadio Bentegodi did not see the incident, but it was caught on camera.
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