Comment on WordPress Hacks by SEO Dave.
I would suggest changing the posts status to either Password protected or Private. I’d go with Password protected.
You could also recover the post and delete the entire contents of the post, save it and trash it again, when Google spiders it again it will be blank. Or setup a 301 redirect or block it via your robots.txt file and make it nocache.
Post a comment for what works as I’ve not tried the Password protected option exactly.
What I have done is turn a load of posts (about 750) that I no longer wanted indexed (jokes added to a site via an RSS feed, so copied content), but didn’t want a load of 404 errors or wasted traffic so changed the status of the posts to draft.
WordPress takes these posts out of the navigation (so no wasted links to them), but they can still be loaded if you know the URL. Long term as Google etc… respiders the site over 6 plus months it won’t find links to these draft posts and will slowly deindex them wasting no link benefit and I didn’t have to setup up hundreds of 301 redirects :-)
Moral of the story, don’t write on the Internet under the influence. That being said would be a pretty boring place if everyone followed that little rule :-)