Moving and removing object references

I have a 2-dimensional array of Objects. Their location in the array determines where they appear on the screen. When I want to move an object down, I am trying something like this:

[AS]LocationArray*[j+1] = LocationArray*[j];
LocationArray*[j] = null;[/AS]Of course, with the way AS3 handles objects and references, it removes the object completely. How can I simply move a reference (or remove an reference) without destroying the object?