Hidden Ball Trick

[truspartan]

Hey guys --- first time poster. A basketball official that I know put me on to this site as a good resource. My background is much less official/professional than probably everyone here -- I'm a dad who has coached my son for the past 6 years because they needed people to coach. I've learned a ton about strategy and rules and continue to learn. My son is now in 13-15 baseball and I coach his team. It's an independent (from Little League) baseball league and we are governed by NFHS rules. But I have a question on the "hidden ball trick"

Here's the situation --- pitcher and infielder meet in infield to "discuss" and switch the ball from the pitcher to the infielder to deceive the runner into thinking the pitcher still has the ball. Runner leads off and infielder with ball tags the runner claiming he's out. However, the pitcher was on the mound (not the rubber) without the ball. Balk or no balk? Does the pitcher have to be on the rubber without the ball? Or just the mound?

I've heard answers both ways and don't have a copy of the NFHS rules to verify. It's a bush-league move at least, but is it against the rules?