LaMelo Ball Cops Baller Diamond Grill With 14k Gold, Welcome To The NBA!

You make it to the NBA, you get iced out ... and that's exactly what LaMelo Ball did -- copping an incredibly shiny diamond grill to kick off his rookie season!!

Of course, the youngest Ball bro. already knows how to be a pro -- he played in Lithuania and Australia before going #3 overall to the Charlotte Hornets last month.

But, making it to the Association calls for a BIG "treat yo self" moment ... so the 19-year-old enlisted AP The Jeweler from Atlanta to come up with an unforgettable piece.

AP tells TMZ Sports ... Melo eventually decided last month it was time to get his first grill, so he got Ball's mold and went straight to work.

The finished product is a pair of 14k white gold chompers (8 top teeth, 8 bottom) with VVS diamonds in a honeycomb set.

As for how many rocks?? AP tells us it's "The most diamonds I've ever put in a grill."

We're told AP personally flew to Charlotte to hand-deliver the finished product on Monday ... and the dude is jacked about the finished product.