Selected answers from the Dumb SEO Questions Facebook & G+ community.
Casey Markee: Correct. If the page is not INDEXED it won`t be chosen as a sitelink.
I have done this in the past successfully myself.
Michael Martinez: It`s a shame they took away the ability to opt a URL out of being used for a sitelink. Noindexing seems like such a drastic response to an unwanted sitelink.
Raajul Sharma: Or you can go to the search console/ webmasters and demote the link there, not sure, if it`s still there in the new webmasters, however that is the quickest and easiest way to do it.