Mac McClung's vert may be just a smidge less next dunk contest ... 'cause the high-flying hooper just got his whole arm tatted in NYC!
TMZ Sports has learned the 25-year-old guard hit up tattoo artist Michelle Santana out in SoHo after peeping some of her work on social media.
We're told McClung wanted an arm sleeve with sentimental meaning ... so the two got together at Bang Bang Tattoo and created a showpiece.
The sleeve on his right arm features a lot of intricate work .