It seems that Materazzi called Zidane a “dirty terrorist”, according to players familiar with the incident, sparking “the headbutt heard around the world”. It seems very possible, Zidane is an Algerian Muslim, and I’m sure his heritage is a sensitive issue for him.
Tua sorella è una prostituta! Sporco mussulmano! Marco Materazzi
that means: ur sister is whore. u filthy muslim! That is what he said