Sorry, I looked at it again, the guy was not expecting it at all. Look at the force Zidane put into the butting.
LOL
Sure it would've staggered him, but he went down like he was friggin shot.
He embellished it. There is absolutely not one doubt in my mind about it.
It doesn't lessen the stupidity or the fact that the act was a definite foul, but the act was truly unnecessary and was VERY soccer-esque.