The announcement on Monday that Fremantle Ryan Crowley had tested positive to a banned substance from a game day test brings the spectre of ending popular tagger’s career.

Crowley tested positive last year to as an as yet unknown banned substance, allegedly from a pain killer medication, in July and was confirmed with a ‘b’ sample test in September.

Sports doctor and media commentator Dr Peter Larkin says that the precedent set for this type of offence would paint a pretty bleak future for the 12 season veteran.

Talking to 6pr Dr Larkin said there were no excuses for Crowley to take a medication that is on the banned list.

St Kilda’s Ahmed Saad returns to AFL ranks this year after serving a 18 month suspension for a similar breach of the AFL drugs code.

Saad tested positive to having a banned substance in his system after consuming an energy drink given to him by a Saints staff member.

‘If Crowley receives a suspension for his offence it could be the maximum of two years which you can’t see the 31 year old coming back from.’ he told the Breakfast program.