Sub Navigation not getting class here on detail page

I have a problem with getting the class ‘here’ to remain on the sub navigation when I’m on a listing detail page.

A bit context: I have a sponsors section that is a child of my club-information section. The sponsors page itself is an index page for all my sponsor listings. so URI looks like this – domain.com/club-information/sponsors/

The Problem: When I hit a listing detail page – domain.com/club-information/sponsors/mysponsor/ – the ‘sponsor’ link in the subnav doesn’t have the

class="here"

attached to it anymore while on this page, is that how it is supposed to work? I have read over the documentation time and time again but can’t seem to find the solution.

The setup:

{exp:structure:nav_sub start_from="/{segment_1}" show_level_classes="no" show_overview_link="yes"}

Thanks Dan