Fremantle tagger Ryan Crowley has begun his doping hearing. Picture: Paul Kane/Getty Images AsiaPac.

Fremantle’s Ryan Crowley has begun his doping hearing after testing positive to a banned substance last year.

The Dockers’ tagger tested positive after his side’s clash with GWS on July 13 last year, before having his B sample tested in September, which was also found to contain a banned substance.

He is currently serving a provisional suspension until the completion of his hearing, where a further suspension could be handed down if found guilty.

The midfielder claims to have ingested the banned substance through a pain killer.

The tribunal is not expected to reach a decision on Crowley’s future for several weeks.

He faces a maximum suspension of two years if found guilty, which will most likely end the 31-year-olds career.