Allen would have won the event in London but the blood found on the flank of the horse led to a mandatory disqualification.

The decision prompted a backlash on social media and has seen some call for a change in the blood rules, after Allen said he must have "slightly nicked" Quiet Easy.

An appeal by the Irishman was dismissed and although the FEI have acknowledged that there was no attempt to harm the horse, they insist that the rules must be followed. 

"I have absolutely no doubt that the protocols regarding blood on the horse were followed correctly at London Olympia," said FEI Secretary General Sabrina Ibáñez.

"Of course this incident has created a considerable amount of discussion on social media because Bertram Allen would otherwise have won the Grand Prix, so there is a high level of sympathy for him, but the FEI Officials were in Olympia - as they are at every event run under FEI Rules - to ensure a fair and level playing field and that the welfare of the horse is protected.

"Blood was found on the flank of Bertram Allen's horse and, under FEI Jumping Rules, that results in mandatory disqualification.

"The situation was reported to the Ground Jury by the FEI Steward who had conducted the normal post-competition check on the horse and Bertram Allen was then informed of his disqualification in person by the President of the Ground Jury and the Foreign Judge. 

"Let me be clear, disqualification under this rule does not imply that there was any intent to injure the horse, but it is crucial that the rules are enforced in order to ensure that horse welfare ‎is protected. 

"It is very easy for any sports official to be criticised when they are simply doing their job.

"Everything at Olympia was handled correctly and in accordance with the rules, but there is no doubt that it was an unfortunate end to a wonderful event." 

Michael Whitaker was promoted to first place following the disqualification but he gave his winner’s rosette to Allen.

“I am devastated by the decision of the ground jury to eliminate me and my horse," said Allen.

"Quiet Easy’s performance was truly outstanding.

"At some point during my very fast round against the clock, my leg must have slipped giving my horse the tiniest of nicks on his side which bled ever so slightly.

“I totally understand the rules in relation to the treatment of horses in competition, but I’m disappointed that the officials didn’t use any discretion on this occasion.”

Germany's Ludger Beerbaum, a four-time Olympic champion, was promoted to second place but was unhappy with the verdict.

"Bertram and his horse were the best combination," he said.

"I had to put my glasses on to see where the tiny mark was.”