Board Game Arena

Recently i've encountered a few games where I won, yet gained 0 rank when playing in an arena game, in this case Race for the Galaxy.
Is there a reason for me to not gain rank?
It looks like it might have something to do with me playing a player that is in bronze. But if that is the case, then why am I paired against that player?
I'm in platinum and want to rank. I'm playing arena to rank, otherwise I'd be playing non-arena.

Thanks!

You gain no rank for beating people more than two ranks below you

To avoid playing them click the cog icon and select only people within 1 or 2 levels of yourself

Thanks @frogstar_A, exactly what I needed!