Busted fence post--ideas??

I've got a fence post that busted off at ground level.  It is a gate post (latch end), so I want replace it exactly where it was.  Post is at least 25 years old, treated, 8-10" diameter.

 

I'm looking for ideas how to pull that post stump.  I'm pretty sure that the post hole digger won't be able to tear it up.

 

I've never run into this situation before and any ideas will be greatly appreciated.

 

Ralph

Busted fence post--ideas??