[JRutledge]

Before Jump balls.

Before FTs.

Before substitutions.

Before Throw-Ins.

Right after timeouts.

All of these are good times to have players tuck in their shirts in. I personally am not an official that usually advocates taking players out of games because of this alone, but I usually will just simple say this to the players. "If you are getting held by another player, do not complain with your shirt hanging out." Usually they get the point and keep them tucked.

Peace