Epsom racecourse has announced the Investec Coronation Cup will revert to its original slot on the Friday before the Derby.
As a result of the change, the Group Three Diomed Stakes will now take place on Derby Day instead, which this year will be run on June 3.
The Group One Coronation Cup has been run on a Saturday since 2012.
Andrew Cooper, head of racing and clerk of the course at Epsom Downs, said;"Between 1997 and 2011 the Investec Coronation Cup was run on the Friday, and was moved to the Saturday in 2012 as part of Her Majesty The Queen's Diamond Jubilee celebrations in that year.
"We believe the reversion of this historic Group One race to the Friday gives a significant boost to the race programme on that day, whilst the Investec Derby stands head and shoulders above all other races on the Saturday."