Question about WordPress Menus and Permalink Structures

I have a large amount of pages and a pretty extensive WordPress Menu set up for my site, because of this the url’s for the pages are getting very, very long on some pages. I have my permalink structure set as postname, but for pages it’s using the hierarchy of the menu. I’m trying to find a way to shorten these long url’s to just the postname for the pages as well. For instance one of my pages is:

http://legendscrazy.net/hasbro/hasbro-marvel-legends-waves-one-to-six/hasbro-marvel-legends-wave-nine-nemesis-series/

and I want it to be just:

http://legendscrazy.net/hasbro-marvel-legends-wave-nine-nemesis-series/

Any suggestions? Thanks in advance for any help!