Blog posts are being listed under content
The fact that blog-post-title appears suggests that the module PathAuto is somehow involved.  Try to disable that module (If you're on Drupal 7, navigate to Home » Administration » Modules, locate PathAuto and remove its tickmark, then press "Save configuration" and clear all caches.)

If the blog posts now appear under /blog, you know why.

After you've etablished that PathAuto is indeed resposible, you can re-enable the module (all its settings will be left intact), and you can then proceed to change its settings to put blog posts in the place you want them.