How to add separate blog page without static front page?


I'm running the Network theme on a multisite and I have a problem with the blog page for the main site. I want to keep the current front page as it is because it shows the posts from all sites but I still need a page to show the main site blog.
I know that you can add separate blog page by using the static front page but that doesn't work in this theme and in my case.

Easy access to the main site blog is kind of missing from the readers with this theme...

Any ideas how to fix this?