There could be a hip-hop hoops battle brewing ... because Justin Bieber and Quavo were just put on blast by super hot ATL rapper Famous Dex ... who says he'd punish both guys in basketball.
We ran into Dex down in Atlanta, and after he showered a lobby with cash, we decided to ask him some sports questions ... while he put the money back in his bag.
Our guy wanted to know if Dex ... a notorious hooper ... thought he could take two other big time ballers -- Quavo & JB -- on the basketball court. Here's a hint, he's confident.
"Man I'll bust Quavo ass out. Quavo don't wanna see me," Dex said, then throwing Justin's name in too.
"Justin Bieber will get blown out 24-0, 35-0."
Your move guys, we just wanna watch.