The prospect of a rule preventing low-rated horses from running in the Investec Derby is unlikely to be implemented until 2019 at least.

The debate over a performance qualification to sift out horses not considered good enough to contest the race occupied much of the media coverage prior last week regarding Diora Lia.

The filly, a 1000-1 chance, had performed so poorly in two career starts she did not even qualify for a handicap mark from the British Horseracing Authority (BHA).

Ultimately Diora Lia went from headline news to damp squib when she was withdrawn on the morning of the race due to a pulled muscle but there is a body of thinking that a horse like her should have been blocked from running in the Derby.

In the Grand National a horse has to be rated at least 120 to be eligible to run and the BHA has already considered the idea at a meeting of the Flat Pattern Committee in April but would only look to implement such a rule for the Derby or other major races following a consultation process within the sport.

Another factor which might prevent the implementation of a performance condition for next year’s Derby is that the race closed last December which could prove a minefield for the BHA should they change the conditions of the race after entries have been received.

Jamie Stier, the BHA’s chief regulatory officer, said: “We wouldn’t be looking to change things for 2018 and, if there were to be changes, there would have to be a substantial process gone through to make changes due to race closing early.”

Setting a performance condition would have to allow for horses who could still be improving while weeding out those who might be considered more of a hazard in a field similar to the 18 who went to post year.

John Gosden, whose Cracksman finished third in the race, said: “I think it’s a very difficult question because you don’t want to elitist. But, I think, if you’re rated below 70, that means you’re selling class, that might sensible.”

In other news Brametot got up in the final strides to snatch victory in the Prix du Jockey Club at Chantilly and it was announced that David Nicholls, who won the Ayr Gold Cup six times as a trainer before retiring earlier this year, had died at the age of 61.