You just got knocked the fuck out!

Ray J has been hanging a little TOO HARD with the likes of Floyd Mayweather and 50 Cent . . . cause he started to think he was a TOUGH GUY.
Last night shortly after rapper Fabolous performed at the Palms casino in Las Vegas - he and Ray J got into a FIST FIGHT. Here's how it all popped off. Ray J was drunk and started talking RECKLESS . . . claiming that he was more popular than rapper Fabolous.

In the beginning it was just JOKES . .. but then 50 cosigning ass started INSTIGATING. Saying   'OOOOOH... Fab how are you gonna let him say that to you....Every time Ray J would say something.


Well it worked because what started out as just JOKES - ended up with FISTS. The insider explained, "Fab was like "Fuck you' to Ray, and Ray got in his face. Next thing you know, Fab two pieced him. Actually is was a three piece cause he hit Ray once on the ground."

Ray J was knocked unconscious. And what happened next, we have to say ALLEGEDLY . . . when Ray was unconscious some people RELIEVED HIM of his jewelry.

Police were called and had to ESCORT Ray out of the casino . . . No word on hether Ray will be pressing charges for the ass whooping . . . or for being RELIEVED of his jewels.