Chicago Bulls star Jimmy Butlerwants to supportyour package ... becoming the latest NBA star to design a high-end men's underwear line ... TMZ Sports has learned.
We're told Butler -- a 2x All-Star -- inked a deal to create a signature line of drawers with underwear brand PSD -- who already have lines with ballers Kyrie Irving and Chandler Parsons.
PSD's prez, Curt Flaitz, tells us Jimmy was very hands on ... leading the design effort on all 6 pairs of undies.
"Jimmy has a great eye for what's going on in the fashion world.