About a quarter of the players likely to be picked in this year's AFL national draft could be taken by clubs with priority access and not freely available to all.

More than 20 players likely to be taken in the draft will come from Next Generation Academies (NGAs), are father-son prospects or part of the northern club academies.

Melbourne's Charlie Spargo is one of the many graduates of the GWS Academy. Credit:AAP

The dramatic rise in the number of players tied to clubs through various academies has some clubs concerned that NGAs, designed to encourage clubs to invest in finding and developing young footballers from indigenous or multicultural non-traditional football backgrounds, are morphing into de facto zones.

"We got through the compromised drafts of the expansion clubs but the draft is now more compromised than ever," one recruiter said.