Dude from The Wanted -- 'Free Lindsay'

One of the guys from The Wanted has Lindsay Lohan's back ... unfortunately for her, it's not the guy she's been trying to bang.

We broke the story ... Lindsay has been gunning to nail Max -- the one with the shaved head -- for the past couple of days ... and partied with the guy at Avenue nightclub the night she was arrested.

But last night, one of Max's fellow boy-banders -- Jay -- let everyone know the guys are still supporting their most infamous fan by wearing a shirt on stage at their concert that read, "Free Lindsay."