Last year's Melbourne Cup first and second, Dunaden and Red Cadeaux, feature among 13 declarations for Saturday's Hardwicke Stakes at Royal Ascot.
The Mikel Delzangles-trained Dunaden also landed the Hong Kong Vase last term, but has this season failed to fully fire in two starts over this mile-and-a-half trip.
By contrast, Red Cadeaux has won the Yorkshire Cup for Ed Dunlop and also finished an admirable second to St Nicholas Abbey in the Coronation Cup.
He is one of two runners for Dunlop, with ex-French filly Testosterone due to make her debut for the Newmarket handler.
John Gosden is another with two irons in the fire as he prepares to saddle the progressive Aiken, who has only been beaten once in seven starts, and Coronation Cup third Masked Marvel.
However, the latter is not a certain starter as Gosden has warned last year's St Leger winner will only run if the ground is suitable.
The trainer said: "He's a horse that appreciates top of the ground, nice summer ground, which we don't seem to be getting a lot of at the moment."
Sir Michael Stoute fields Sea Moon and Fiorente, with the former, who finished second in the Breeders' Cup Turf last term, the choice of Ryan Moore.
Aidan O'Brien relies on Memphis Tennessee, while Hunter's Light will represent the Godolphin team.
Allied Powers, Calico Cat, Jakkalberry and Quest For Peace complete the line-up.