I wasn't working this game, just watching...FED Varsity, Right handed pitcher, runner on first. In an attempt to pick off R1, F1 (in the set position, has taken his sign, and has come to a pause) spins on the rubber and throws to first. F1 never left contact with the rubber, just simply pivoted and spun, i.e., F1 did not step off the rubber and then throw or do s snap move to first...bottom line, back foot was in constant contact with the rubber during the entire pick off attempt. Balk? I would appreciate rule references if anyone can provide them. Thanks!

Did he step [gaining distance and direction] toward 1st with his non-pivot foot ahead of his throw? If yes: no balk. No step is a balk.
There is nothing wrong w/ his "back" [pivot] foot remaining in contact, tho' I'd think it might be a little awkward.

Yep, cb's got it again. No balk.

It's a common misconception that a pitcher must disengage before throwing to first. There's nothing wrong with having his pivot foot on the rubber the whole time throughout the pickoff. Cb pointed out the non-pivot foot gaining distance and direction. As long as that was ok, i have no call.

Thanks cb...looks like I have a coach to apologize to (I was talking to him after the game was over and mentioned that I thought that would be a balk). I guess I thought this would be a balk because when I played I was always taught then when on first against a righty, to always look at the back (pivot) foot. If it moved, get your arse back to first. Also, it is a completely awkward looking move, but that obviously doesn't make it a balk.