The long-standing AFL career and reputation of Graeme Allan hangs in the balance amid allegations that the former Giants football boss deleted text messages concerning an attempt to protect the club's former No.1 draft pick Lachie Whitfield from drug-testers.

Allan, Whitfield and the club's then welfare manager Craig Lambert face bans of between two and four years should the evidence against them be proven.

Allan, centre, denies deleting the texts. Credit:Jesse Marlow

The AFL, which has known about the allegations for almost 15 months, will now hand details of its lengthy investigation to the Australian Sports Anti-Doping Authority.

The text messages allegedly deleted by Allan would have been part of evidence in the case that Whitfield's former girlfriend contacted the club and later submitted evidence that the player was helped by club officials following drug concerns. Lambert is also alleged to have deleted text messages.