how to re-import photo so it appears in original position?

I recently deleted a photo from iPhoto 9, because it appeared to have become corrupt.

(The thumbnail became black, and although the picture opened on click none of the usual iPhoto maintenance would fix it.)

I then re-imported the pic. But it appears under 'Last Import' and I can't see how to get it to appear again in its original position.

All the data/information - date/time etc - is the same as the original. So how do I move it, to get it back into sequence?