I'm stumped by this stupid newbie error I'm seeing... trying to figure out where to "look" next... (undefined method xxx_path )

On one of my new.html.erb files backed by a "matches_controller" I'm
getting the error:

undefined method `matches_path' for #<ActionView::Base:0x2cfc748>

I don't understand where to start looking to try to understand why I'm
getting this error. Even if I back everything out of the page and just
have:

<h1>New match</h1>
<% form_for(@match) do |f| %>
<% end %>

I still get the error.

What am I supposed to do to start tracking now where the issue is? Is
it that I'm getting an error message that isn't directly related at
all to the 'matches_path" issue.
Other pages aren't having this issue, so I'm a bit stumped.

I'm a rails newb (but seasoned java person so I have no problem
looking in logs for errors.. but the errors don't seem to be helping
me track down the 'reai' issue.)

Thanks for any direction of what to start looking at (is it maybe an
obscure error in my controller or another page causing the problem?)