The NSW medical watchdog is investigating the role of any and all health providers who may be linked to allegations of serious misconduct by NRL player-turned-coach Sam Burgess.
The state's Health Care Complaints Commissioner confirmed on Thursday it had established an inquiry in response to media reports naming Burgess, and other information.
It said the inquiry would allow it to examine all the allegations raised and the role and actions of any health providers who might be involved.
A report in the Sydney Morning Herald suggested South Sydney's club doctor Andrew McDonald was the focus of the inquiry.
In a report last week, The Australian newspaper outlined a number of serious allegations of drug use and domestic violence against Burgess, who has stood down from his assistant coach position at South Sydney and a media role.
In the report, Dr McDonald was alleged to have treated Burgess with a tranquilliser in 2018 in questionable circumstances. Burgess has denied wrongdoing in relation to any of the recently-aired allegations.
The commission declined to name Dr McDonald on Thursday but said it was working closely with NSW police and other regulatory bodies.
"To preserve the integrity of the commission's own complaint assessment processes and the processes of NSW Police, the commission is unable to disclose further specific details at this time," it said in a statement to AAP.
On Saturday, NSW Police launched Strike Force Irrabella into the allegations against Burgess.
The NRL are also investigating both Burgess and the South Sydney club over the allegations.
NRL chief executive Andrew Abdo stressed the seriousness of the allegations but said no action would be taken against Burgess or the South Sydney club on allegations alone.
South Sydney will cooperate with the investigation and said it was treating the allegations with the utmost seriousness.
"There is no place in our society for violence, harassment or abuse against women," a statement read.
"The club takes issues of drug use very seriously and has well-established policies and procedures in place around the use of performance-enhancing or illicit/recreational/prescription drugs."
Burgess, an integral part of Souths' NRL premiership success in 2014, denies any wrongdoing.
His lawyer told The Australian "the allegations are false and constitute indefensible defamation against my client".
The former Rabbitohs captain stepped down as one of Wayne Bennett's assistants on Friday but the veteran coach said the matter had no bearing on any of the current playing group during its finals campaign.
On Sunday, the Rabbitohs easily dispatched the Newcastle Knights 46-20 in the qualifying final and now take on the Parramatta Eels in a sudden-death game on Saturday.