But not in the middle of a serve, as someone did to Ferrer the other day - a shout of "Roger" just as he tossed the ball. Dreadful.
Have a great time!
But if you do it in the middle of the point, the great man himself may even tell you to "Shut up!".
So, who's going to take a sign of Murray wearing his gold medal with the line "this is just a formality" on it?