Listen up, Lonzo Ball -- Chauncey Billups says he knows THE guy who can help you turn around your historically bad shooting ... and he might even hook y'all up if you ask nice.
"If I was Lonzo, I would call Kevin Martin -- a guy in our league who had like this funky shot but he could shoot the hell out of it," Chauncey told TMZ Sports.
Pretty good advice ... Martin used to be one of league's deadliest snipers and, more importantly, did his thing with a jumper that looks JUST LIKE Lonzo's.
So before you heed the haters and start shooting like all the normies -- "Try Kevin first."