The AFL has fined Essendon $20,000 for conducting medical tests on potential draftees.

The breach of league rules was discovered by Essendon employees during an internal audit of the club’s football department. The Bombers reported the incident to the AFL.

The league controls the medical testing of potential draftees.

League rules stipulate clubs must not direct a player who had attended a combine or state screening session to be tested, evaluated or to do any form of training with either the club or an associated club before draft day.

Clubs were warned against conducting their own medical tests on under-age talent ahead of last year’s draft, after a number of players were contacted by clubs after the state screenings and draft combine.

In 2013, Essendon broke league rules on unlisted players training ahead of the rookie draft. The Bombers were fined $20,000, half of which was suspended.

Monday’s penalty, which was reported on the AFL website, comes as ASADA continues its investigation into Essendon’s 2012 supplements program.