NBA's Nick Young -- Launches 'Official Inquiry' ... to Join Australian Olympic Team

Nick Young wasn't joking around about wanting to compete for Australia's Olympic basketball team -- 'cause the NBA star's camp has formally contacted Aussie officials to get the ball rolling ... TMZ Sports has learned.

Young -- who's famously engaged to Australian superstar Iggy Azalea -- has recently been floating out the idea to compete with Australia, but everyone thought he was just goofing around.

But we spoke with a top official for Basketball Australia who tells us, "Nick's representatives have been in contact with an 'official inquiry.'"

The official told us Nick would have to become an Australian citizen to be eligible for the team -- and the process was thoroughly explained to Young's camp.

For the record, it's not an easy process -- according to the official, Young would have to start by living in Australia for "an extended period of time."

And after that, Basketball Australia tells us there's no guarantee Young will make the squad -- "He would be considered for selection on MERIT like everybody else."

Young is already drumming up support from famous Australian hoops stars including Golden State Warriors player Andrew Bogut -- who suggested Iggy could also rap the National Anthem.