First Base Rule: Orange vs. White Base - Correct Ruling & Explanation

Question
I coach a high school team.  We had a situation where the 1st baseman's foot was touching only the orange bag on a throw to first base.  The runner was clearly out by the throw; however, the umpire called her safe because the 1st baseman's foot was on the orange not on the white.  I thought it was to be considered one base.  Can you tell me the correct ruling and where to find it?

Answer
Hi Anne,

If a play is being made at 1st......

if the throw is coming from fair territory (see exception below) the defense must use the white portion and the offense the colored portion.

If the throw is coming from foul territory or an errant throw that pulls the defense into foul territory the offense and the defense can use either base.

ASA 8-2-m

Once 1st base has been occupied it now becomes 1 large base.

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