Posts in 2 categories – what’s the url?

Hi everyone,

I currently want to have it set up so my permalinks will display the category/post_id or whatever, which works great by doing the custom structure: /%category%/%post_id%

However most of my posts have more than 1 category, News and another category such as Tennis or Volleyball. The problem is all these posts have a link as http://www.url.com/news/post_id – I don’t want news in the url, but rather the other category I have, any idea how to do this?