Aidan O’Brien will saddle four contenders among the nine declared runners for Saturday’s Group 1 Coral-Eclipse Stakes at Sandown Park. The Irish trainer, who holds a record of nine Eclipse victories, aims to extend his success in the race that traditionally features a key showdown between the classic generation and their older rivals.

O’Brien’s leading entry is Constitution River, the winner of this year’s French Derby, who enters the race as the 5-4 favourite according to the sponsor’s betting market. Constitution River is expected to be a central figure in the contest, reflecting the strong form he has demonstrated throughout the season.

Challenging Constitution River is Gethin, the 2-1 second favourite in the market. Gethin was recently acquired privately by Wathnan Racing after winning a listed race at Kempton Park in April. The acquisition has looked promising, as Gethin, wearing the Wathnan colours for the first time, finished just a neck behind Ombudsman in the Brigadier Gerard Stakes at Sandown Park, signaling his readiness for the higher-class Eclipse.

Roger Varian’s Saddadd is also among the main market contenders, trading at around 4-1. Saddadd is expected to factor into the battle among the established older horses in the field.

The Coral-Eclipse Stakes, run over 1 mile and 2 furlongs, will serve as one of the mid-season highlights, providing fans with a clash between top-class horses at different stages of their careers. The full line-up features a blend of promising younger horses and seasoned performers, while the rivalry between O’Brien’s quartet and their market rivals adds further intrigue to the race.