The news comes as NRL chief executive Dave Smith flew to Canberra to discuss the latest developments with Australian Sports Anti-Doping Authority chief executive Aurora Andruska on Friday.

Earl is facing the prospect of a four-year ban from sport for doping offences, including trafficking, during his time at Penrith in 2011. The Canberra winger, who is hopeful of a 75 per cent discount on his ban for providing ''substantial assistance'' to ASADA, has denied providing banned substances to other players.

The NRL has issued Earl with an infraction notice for the use and trafficking of performance-enhancing drug CJC-1295.

As revealed by Fairfax Media in June, sports scientist Stephen Dank referred Earl to Dr Ijaz Khan, a practitioner at the Injury Care clinic at Cabramatta, to treat Earl's shoulder injuries. Earl's lawyer, Tim Unsworth has flagged their intention to to explore taking action against Dr Khan.

''Yes is the unequivocal answer,'' Unsworth said when asked if they may take action against Khan.

Fairfax Media revealed in March that Earl was on the cusp of switching to the AFL after participating in a secret try-out for Essendon arranged by Dank.

The Canberra three-quarter was at the crossroads at the time, playing most of his football for the Windsor Wolves after struggling to cement an NRL spot at Penrith. The secret trial, a one-hour session at the Royal Botanic Gardens, was witnessed by a number of Bombers officials including Adrian Dodoro and Simon Goodwin.

''He had a fair leap. He was not bad with his grab of the AFL ball but he needed a bit of work on the punt,'' an observer said. However, the switch never occurred.

A day after announcing that Earl had been stood down, Smith headed to the nation's capital to discuss the issue with ASADA officials.

''I went down to meet Aurora and the ASADA team as part of regular discussions that we've had,'' Smith said. ''There is nothing new or unusual about it, it's just part of a normal meeting with their team. I took my team down and we had a normal discussion.''

Asked what role the Earl developments played in the discussions, Smith said: ''Yesterday's development had been building for some time. We've been very aware and working very closely on the ongoing investigation. In some ways it's just a continuation of the investigation.

''It wasn't a specific discussion about yesterday's development. It's all part-and-parcel of the ongoing discussion.''

While the AFL have banned Essendon from its final series as part of a range of sanctions against the club, Cronulla will enter the NRL playoffs with a cloud still hanging over them. ''It's progressing and maturing as an investigation as they get more and more information,'' Smith said.

''I've said I'll only deal in facts and what we saw yesterday was an admission from a player, and we dealt with it promptly. That's the consistency we are going to apply. Where there is a fact and information that can lead to an infraction, we'll issue an infraction. ASADA will continue with their investigation. They will pretty much finish their interviews with the players in the middle of next week and then they have got some external people they will start to interview … ''We're working pretty closely with them and we're working as hard as we can.

''What we're trying to do is do the right thing, and [to] make sure you do it properly and fairly, and take it seriously.''

Attempts to contact Dr Khan were unsuccessful.