Former Harlequins director of rugby Dean Richards has admitted he ordered the fake blood-injury substitution of winger Tom Williams that led to him receiving a three-year worldwide ban from rugby this week.

But the 46-year-old former England number eight insists he was not aware of steps - including a deliberate cut to Williams’ lip - to cover up the incident until eight days later.

Only then did he agree to protect the ‘professional position’ of those involved by orchestrating a plan to conceal the crime of passion that saw fly-half Nick Evans re-introduced to the action in the latter stages of Quins’ 6-5 Heineken Cup quarter-final defeat to Leinster.

Richards has since claimed full responsibility for the events that first saw him resign from his post and subsequently banned from coaching.

“I have always been passionate about rugby and in the dying minutes of that Heineken Cup quarter-final - a stage Harlequins had never reached before - I allowed my passion for the club to compromise my judgment,” he told the BBC.

“I ordered a blood substitution to be made using fake blood. Thankfully the substitution did not affect the outcome of the game.

“Some eight days later I was told by Tom Williams that, in the heat of the moment and at his direction, he had his lip cut to make it appear as if there had been a real injury if anyone asked to look at it.

“Believing this to be true, I felt a managerial duty and sense of loyalty to safeguard the professional position of those involved.

“From then on, with the agreement of Tom Williams, I suggested the fabrication of a story, which led to us all withholding the true facts, a position that was obviously wrong.

“I have since made clear that I accept full responsibility for what happened and have apologised for my actions. I honestly believed that I was acting in the best interests of the club and my colleagues, a clearly mistaken belief.

“I am mortified that this matter has brought damaging publicity on Harlequins, members of its staff, my own family and the wider game of rugby.”

Richards is yet to decide whether he will appeal against the ERC appeal hearing panel’s ban.