The AFL and former anti-doping boss Richard Ings have confirmed Ahmed Saad is within his rights to play for St Kilda, despite returning an irregular drug test result.
Saad will most likely know in the next week whether his B sample is also irregular.
If that's the case, the Australian Sports Anti-Doping Authority (ASADA) will serve an infraction notice and Saad will go before the AFL tribunal.
Under anti-doping rules, the Saints small forward can keep playing until ASADA serves the infraction notice.
Brisbane fans booed Saad at the `Gabba last Saturday night after he was a late inclusion for the match.
He was not even one of their three emergencies until the Saints named him in the squad on Friday afternoon.
An initial irregular test result is supposed to be confidential until a charge is laid, but Saad's case was leaked to the media last week.
"They're completely compliant with WADA in that decision and whether he played or not was a decision for the club," said AFL deputy chief executive Gil McLachlan.
"It's pertinent to note here that normally this would be confidential - the fact it was made public makes it slightly different.
"But he's well within his rights and there's a process to play out here.
Ings, the former ASADA chief executive, also backed Saad's right to play while ASADA continued to process the case.
"A positive test for a specified substance might attract a ban of weeks to a couple of months, depending on the circumstances," Ings told the AFL website.
"So if you provisionally suspend someone, they may actually be provisionally suspended longer than the actual ban would have been."
The Saints said Saad was brought into the side after a gastro bug swept through the club.
It was his first senior game since round 15.
Saints coach Scott Watters said on Friday that Saad's anti-doping case was an isolated issue for the club.
Saad returned an irregular sample last month, with the Saints saying it was for a substance that is permitted for use out of competition but not in competition.
It is understood that the case stems from an energy drink that Saad took before the round 15 match against the Dockers.
