So i've been struggling with this one...

My female roommate occasionally has friends that stay over from out of town. They sometimes spend a few nights over. We all casually hang out and a couple of her friends really like flirting with me. The problem, however is, i am immediately placed into the friend zone. I try to be distant (hard to get), neg them whenever i see them, but so far all of my attempts have been rather unsuccessful. Any advise on how my strategy should be from the beginning... the moment i meet them? or is it just smarter to keep them as friends?