Help me understand the BU positioning on this play

[Andy]

I think the important thing to remember is that you have another runner to worry about and need to be aware of as well. In a two umpire system, you both can't focus strictly on the lead runner caught in the rundown.

As PU, I would come up to third in anticipation of a possible play there, then take the rundown allowing my BU partner to have the batter-runner. It's also possible that BU could stay in the neighborhood of second to be able to get that end of the rundown while staying aware of the BR.

Either way, the two of you have to communicate here and let each other know what you are doing.