Batting the ball BEFORE the snap

[a4caster]

We had this last night and had a complete brain freeze on penalty enforcement. To set it up, team b scored but did not make the conversion, so team a is on top with 30 sec. left. Team a gets ball back and will take a knee. Nose Guard comes up when everyone goes down and bats the ball from the snapper before he can snap it. My first reaction was encroachment (breaking the plane of the neutral zone.) But somewhere in the vastness of my mind, I recall something brought up in the past few years that this is a potential travesty of the game, and as such should be treated as an unsportsmanlike. Since the NG was being a jerk all night, that's the route we took, and the coaches didn't disagree. But the true penalty is in doubt.
Your thoughts...