I am trying to build a pivot table/chart in which the PageFields will only
list the remaining or available PageFieldItems after other choice
PageField--constraints--are applied.

For example:
Having the PageFields:
Baseball Teams
Players
And when a specific team is chosen only players on that specific team are
shown.


Brain Storm:

My thought is to build a combo/dropdown box to replicate the page field and
then take the values assigned to that and then do a custom filter to develop
a new list which subsequently populates the combo/dropdown box. Meanwhile
take any choice values and apply them toward pivot table/chart build.

Does anyone have any ideas? Am I reinventing the wheel?