I reckon he was laughing because he and Rafael are Brazilian Teammates and he knows he got him there. But if you didnt notice after he smiled he was about to get up and then had a look over and went back into a state of 'agony' if you will. But fuck what other people think. He's a fucking legend ! And Howard Webb was absolutely dreadful today and David Luiz was fucking frustrated and in the end justice was served (surprisingly enough because.... afterall it is Man Utd and Howard Webb were talking about here.