that doesn't sound right at all
you can tryout for a g-league squad once you turn 18
and then get called up as soon as the main squad feels like
so if you're really a blue chip they'd just sign you and then maybe let you play in the g-league until they thought you were ready
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Nah they cant call you up. You can play in the the dleague when you're 18 but you still have to go through the draft to play in the league.
If by a certain age (cant remember what age but i think its 23) you haven't declared for the draft, you become automatically eligible for the draft.
The only way "around" the draft is to not declare and then not get drafted when you become automatically eligible .