The doctor at the centre of allegations about the doping of as many as 150 athletes, including past and present Premier League players, is an unregistered former GP already embroiled in a misconduct hearing with the medical watchdog.

Mark Bonar (38) was recorded and quoted by the Sunday Times as saying he had treated sportspeople, including footballers, boxers, cyclists and tennis players, with banned substances such as erythropoietin (EPO), steroids and human growth hormone.

He told the paper he had not breached General Medical Council (GMC) rules, and that doping regulations were the responsibility of individual athletes.

But Bonar, who the GMC revealed on Saturday is not registered to practise medicine, also faces a misconduct hearing for allegedly failing to inform a patient her cancer was terminal, so that he could keep charging her for treatment.

Bonar describes himself on his LinkedIn page as having spent just over four years as a GP at a practice in Bayswater, central London. From 2011, the page says he was a “concierge, doctor and managing director” at an anti-ageing centre called the Ultra-Wellness Clinic .

The centre has been based since 2014 at the Omniya clinic , a private medical practice in Knightbridge. This is where, according to the Sunday Times, Bonar allegedly wrote prescriptions for human growth hormone and a banned steroid for a German runner who posed as an athlete who struggled to recover from training.

Removed

The Omniya clinic now appears to have removed Bonar from its list of resident practitioners, and did not answer calls yesterday.

According to the GMC’s register of doctors, since June last year, Bonar, described as qualifying in 2001 from the National University of Ireland, has been registered without a licence to practise, meaning a doctor is on the official register but is unable to carry out medical work such as writing prescriptions.

Bonar is subject to a series of parallel conditions, including telling the GMC if he takes up a medical job in the UK or abroad, and being prohibited from offering a treatment called total parenteral nutrition, or TPN, outside a hospital.

The latter condition refers to a medical practitioners tribunal hearing Bonar faces later this month, not connected to the doping claims, into allegations he failed to tell a patient her cancer was terminal and instead treated her with TPN.

An initial hearing late last year was told that Bonar continued to charge the woman for the “unconventional” treatment, even when nurses told him she needed palliative care.

“Your opinions are valueless because you are just nurses and I am a doctor,” Bonar allegedly told them. Bonar’s LinkedIn page also describes him as “executive chairman” of a medical tech company called HelloDr, which aims to provide web- based consultations with doctors 24 hours a day.

The Sunday Times report contained allegations that Bonar claimed to have treated Premier League footballers, British Tour de France cyclists, tennis players and a British boxer with banned substances including EPO, human growth hormone and steroids.

Leicester, Arsenal and Chelsea have expressed their disappointment at the publication of doping allegations made against them in the report, which they claim are "without foundation". The three Premier League sides were all named in the Sunday Times report.

"Leicester City Football Club is extremely disappointed that the Sunday Times has published unsubstantiated allegations referring to players from clubs including Leicester City when, on its own admission, it has insufficient evidence to support the claims," said a statement from the Premier League leaders. "Leicester City follows robust and comprehensive anti-doping protocols to ensure its full compliance and that of its players with all anti-doping rules and regulations."

Allegation denied

The s report also claimed a former Chelsea fitness coach Rob Brinded had “collaborated” with Bonar but Press Association Sport understands Brinded categorically denies the allegation. “The claims the

Sunday Times

put to us are false and entirely without foundation,” said a Chelsea statement. “Chelsea Football Club has never used the services of Bonar and has no knowledge or record of any of our players having been treated by him or using his services.”

Arsenal also dismissed the allegations. – Guardian Service and other agencies