This might be the biggest baller move yet ... LaMelo Ball and his manager, ex-NBA player Jermaine Jackson, just teamed up to buy the Australian pro basketball team Ball suited up for this past season.

BIG BALLER!!!!

18-year-old Ball was a beast in 12 games for the Illawarra Hawks last year ... averaging 17 points, 7.5 rebounds and 7 assists a game before a foot injury sidelined him for the rest of the season.

Jackson -- who played 5 seasons in the NBA -- explained the move to ESPN, saying Ball loved his time in the Australian NBL so much that he decided to take charge.

The Hawks were reportedly facing financial issues while Ball was on the team ... and now the top NBA prospect is hoping to keep the shop open for his teammates and future players.

"Melo loves the Illawarra fans," Jackson said. "He loves that community. They opened their arms to him. They made us feel like we are at home. When we started hearing about the issues they were going through, we talked about it and decided, 'Let's own the team.'"

Jackson insists the move won't affect Ball's bright NBA future ... saying the plan is to hire the right people to keep the team running.

"He wants to create the best basketball program possible for that community there."

No word on how much it cost to buy the team ... but it can't be cheap.