Password protecting just blog page

Hi! I have a client at this site: http://memphisradiological.com/ who wants to password protect JUST their blog page here: http://memphisradiological.com/blog/

While "Blog" is technically a page, because the page is being overwritten by the index, it never calls the password setting.

I tried making a blog page template, but it still isn't calling the content, so no go. Any ideas? Thanks!