The British Horseracing Authority labelled the Benvenuto Cellini affair at Epsom on Saturday as “probably the most extreme test of this rule imaginable”.

Aidan O’Brien’s Derby favourite was declared a non-runner by the stewards around 20 minutes after the race, meaning backers of the winner Christmas Day, a stablemate of Benvenuto Cellini, suffered a 25p Rule 4 deduction, although that was waived by several bookmakers.

His near hind-leg was briefly caught on the inside shelf of the stalls as the gates opened for the premier classic, causing him to slightly miss the break.

He ultimately finished a well-beaten 10th in the hands of Ryan Moore, but was deemed not to have had a fair start by the officials, whose powers to make such a judgement came into effect from May 1st, 2024.

The new rule was brought in following an incident at Royal Ascot in 2018 when Harry Angel got his leg caught up in the stalls just as the field was let go in the Diamond Jubilee Stakes.

The ruling states that stewards can declare a horse a non-runner if a horse is “denied a fair start and its chances are materially affected”.

Extreme test

In a blog published on Monday, the BHA said: “The incident we witnessed on Saturday is probably the most extreme test of this rule imaginable, involving the heavily backed favourite in the Derby. We entirely understand the frustrations of those who were affected by the Rule 4 deduction, and the impact on bookmakers.

“However, this must be balanced against the impact on those who had backed the horse and were denied a fair start, which is who this rule was brought in to protect.

“In 2018 a remarkably similar incident occurred involving favourite Harry Angel in the Diamond Jubilee Stakes at Royal Ascot. While it is fair to say the Harry Angel incident was more pronounced in nature, the principle was very similar.

“This incident occurred prior to this rule being in place, and Harry Angel therefore had to count as a runner. This led to significant, sustained criticism and complaint from media and punters alike regarding the unfairness that a horse should be deemed a runner when he had not been afforded an equal start and his chance in the race had been materially affected.

“The fact is that there is no one set of rules which will be satisfactory for everyone in such a situation. We understand why those who are impacted by the incident on Saturday are disappointed. Equally, if this rule wasn’t in place, then those who backed Benvenuto Cellini would have a right to feel aggrieved.

“It is the view of the BHA, however, that we should be in line with the majority of the international racing community on this issue, rather than an outlier.”

It added: “Some industry and betting stakeholders have suggested that the rule should now be reviewed. We will of course listen to any concerns which are raised and engage with those within the sport. Our rules are constantly under review and the same will apply here.”