Differing versions of what occurred in the Gold Coast Suns' medical department in the pre-season of 2011 have clouded ASADA's investigation into veteran Nathan Bock.

While the Australian anti-doping authority remains poised to rule on whether to deliver Bock an infraction notice for allegedly injecting a banned substance, the Suns have moved to support him and will sign the former Adelaide defender to a new one-year deal in the coming days.

Nathan Bock. Credit:Angela Wylie

Gold Coast doctor Barry Rigby is understood to have told ASADA he never approved the banned substance CJC-1295, a peptide growth hormone allegedly recommended to Bock to overcome an injury in late 2010.

However, former Gold Coast high-performance boss Dean Robinson has reportedly stated that disgraced biochemist Stephen Dank had a meeting with the Suns' doctor in which he sought and received approval for the drug.