Interference at 1B

Question
Hi Mark,
Situation.  ASA tournament play, 14U girls.  Batter bunts, 1B and 3B run in to cover the bunt, 2B covers the bag at first.  The defensive player places the heel of her right foot on the edge of the bag and places her left foot in foul territory, basically straddling the bag.  The ball is thrown from 3B to make the play at first.  The batter/runner cannot run through first and has to slow down to try to reach her foot in between the legs of the defensive player and is then called out.  I (being the 1B coach) asked the ump if it was interference and he said no.  Hmmm.  The next batter  hit the ball to deep SS and the 1B person did the same thing and my runner was called out.  I told the ump that my base runner has the right to run through the base unhindered and that style of 1B coverage is a ploy to slow down the runner to give more time to make a defensive play.  The ump said there is no rule that says you can't play first base in that manner.  Question, what do I tell my runners to do?

Answer
Hi Bill,

Offensive players interfere, defensive players obstruct.

Obstruction is the act of a defensive player not in possession of the ball or not in the act of fielding a batted ball that impedes progress of the b-r or runner legally running the bases.

POE 36....If a defensive player is blocking the base or base path w/out the ball that is obstruction.

So there is a rule, print this out and show it to the umpire.

Mark