MAHMOOD Al Zarooni was surrounded by a media scrum as he arrived at British Horseracing Authority headquarters to face a disciplinary hearing over doping today.
Al Zarooni entered the building in central London with Simon Crisford, racing manager for the Godolphin operation, but did not speak to waiting reporters.
The scandal has already caused Sheikh Mohammed to lock down Al Zarooni's stables, saying he was "appalled and angered" by events.
The trainer was charged by the BHA after tests on 11 of his horses showed the presence of anabolic steroids.
He could lose his licence as a result of the hearing, in what is one of the most significant doping scandals in recent racing history.
The 37-year-old has officially been charged with rule breaches related to prohibited substances, duty to keep medication records, and conduct prejudicial to racing.
He admitted wrongdoing ahead of this afternoon's hearing, in which he is not being legally represented, saying he had made a "catastrophic error".
Speaking on Monday, he said he did not realise he had broken any rules as the horses were not racing at the time.
Samples were taken earlier this month from 45 horses trained by Al Zarooni at Moulton Paddocks Stables, Newmarket.
Subsequent analysis showed 11 of the samples contained ethylestranol and stanozolol, which are prohibited substances.
In a statement on godolphin.com, Sheikh Mohammed said earlier this week: "I was appalled and angered to learn that one of our stables in Newmarket has violated Godolphin's ethical standards and the rules of British racing.
"I have been involved in British horse racing for 30 years and have deep respect for its traditions and rules.
"I built my country based on the same solid principles. There can be no excuse for any deliberate violation.
"Godolphin is fully co-operating with the British Horseracing Authority to get to the bottom of this matter and take any appropriate disciplinary action.
"I have ordered the Godolphin management to undertake an immediate review of our internal procedures and controls to ensure to prevent any reoccurrence of this type of activity in any stables of mine.
"We will be locking down the Moulton Paddocks stables with immediate effect, and I have instructed that I want a full round of blood samples, and dope testing done on every single horse on that premises.
"I can assure the racing public that no horse will run from that yard this season until I have been absolutely assured by my team that the entire yard is completely clean.
"I have worked hard to ensure that Godolphin deserves its reputation for integrity and sportsmanship, and I have reiterated to all Godolphin employees that I will not tolerate this type of behaviour."
The BHA said on Wednesday that information provided by Al Zarooni to investigating officers showed that in addition to the 11 horses that had tested positive, four other horses - Comitas, Sashiko, Vacationer and Tearless - were administered one of two prohibited substances. They were not tested but Al Zarooni faces further charges in relation to medication records and conduct prejudicial to racing.
Al Zarooni joined the Godolphin team in March 2010 and has trained a host of big-race winners.