Dante Exum has landed a multi-million dollar endorsement deal before playing a single second in the NBA.

Exum, a 198cm tall 18-year-old who is expected to be a top-five pick in June's draft, is leading an Australian wave of sons of US imports in the NBL set to attract plenty of interest from ambitious NBA teams.

The former Australian schoolboy's contract - announced in the United States on Friday - is the latest step in the transformation of Exum into an international basketball superstar.

The deal comes without Exum playing for a US college team and just over two months before the NBA draft on June 26.

Exum's US-born father Cecil played on Michael Jordan's team at the University of Carolina in the early 1980s before moving to Australia to play with North Melbourne Giants, Melbourne Tigers and the Geelong Supercats.

Details of the deal were not disclosed publicly, but it is believed other leading shoe brands were chasing the signature of the former Australian Institute of Sport athlete.

The guard from Melbourne has also signed a lucrative trading card deal.

Ben Simmons, the 206cm, 17-year-old son of Melbourne Tigers legend Dave, was this week named the MaxPreps junior player of the year in the US after a standout season with top Florida high school Monteverde Academy.

He has committed to play for Louisiana State University.

On Thursday, west coast basketball college powerhouse UCLA announced 18-year-old, 206cm Australian power forward Jonah Bolden, son of former NBL high-flyer Bruce who played with South East Melbourne Magic and the West Sydney Razorbacks, had committed to play with the university.

AAP