One of rugby league's most promising young players is facing the prospect of a four-year ban after allegedly testing positive for a banned substance.

North Queensland centre Bacho Salam has allegedly failed a random Australian Sports Anti-Doping Authority test earlier this year in the latest drugs drama to rock the code. While he is entitled to continue his playing career until he receives notification of the result of his B sample, the Cowboys and Salam have agreed for him to stand down.

Positive test: North Queensland's Bacho Salam has allegedly failed a random ASADA test. Credit:NRL Imagery

The 20-year-old hasn't played for more than a month and any suspension he serves can be backdated to his last game.

Salam is alleged to have taken a supplement obtained outside the club that had only recently been added to the World Anti-Doping Agency banned list. It is likely he will seek a reduced sanction, given he inadvertently took an illegal substance, although the onus is on athletes to ensure anything they ingest complies with the WADA code.