--- In llumpires@yahoogroups.com, John Chivers <jchivers@...> wrote:
>
> Oddly, this is something I used to worry about when I first started, 20 years
ago.  Umpiring is so much easier when you don't worry about things you don't
need to worry about, like shortstops slapping their glove, or players sticking
their fingers in the screen of the dugout, or whether sunflower seeds and bubble
gum are allowed.
>
> First off, he probably means "distracting the runner", not "deceiving" him. 
Second, there's no rule against it.  Third, the shortstop is really just helping
the runner locate him.  It's hard to sneak behind R2 when you're slapping your
glove like an idiot.
>
>


Pros do it.

It's not done on a pickoff attempt. It's done other times to get the runner to
move back or lean toward 2B, slowing his ability to advance.