The Jamesfield Place handler was in court in Bury St Edmunds on Tuesday following his arrest in Newmarket's Hamilton Road on June 20.

District judge David Cooper heard that Quinlan's horsebox, which had a horse inside, was involved in a minor incident at around 6.20pm as it drove to the evening meeting at Newmarket's July Course.

Prosecuting, Rachel Mahony said police were called but when they pulled the horsebox up they found a woman at the wheel.

Quinlan, however, admitted he had been driving and a breath test showed he had 54 microgrammes of alchol in 100 millilitres of breath – the legal limit is 35 microgrammes.

The court heard that Quinlan, 56, who last month was celebrating a first success at Royal Ascot, had a previous conviction for drink-driving in 2002.

As well as being disqualified, he was fined £300, ordered to pay £60 towards prosecution costs and a £15 victim surcharge.