Last year's winner Nathaniel is one of 17 remaining entries in the Betfair-sponsored King George VI And Queen Elizabeth Stakes at Ascot on July 21.
John Gosden's four-year-old is due to make his seasonal reappearance in the Eclipse at Sandown this weekend, if the ground permits.
Gosden could also run last year's St Leger winner Masked Marvel.
A surprise absentee is Cirrus Des Aigles, currently embroiled in a doping scandal in France but also on the sidelines with an injury.
There is still a strong challenge from France with Melbourne Cup winner Dunaden, last year's French Derby winner Reliable Man and his Alain de Royer-Dupre-trained stablemate Shareta.
The Prix de l'Arc de Triomphe winner Danedream, disappointing when last seen, is also still a possible and completing the list of international challengers is Deep Brillante from Japan.
Aidan O'Brien's first string appears to be St Nicholas Abbey with Imperial Monarch, Robin Hood, Windsor Palace and Memphis Tennessee still engaged. Camelot has, however, been taken out.
Dubai World Cup winner Monterosso could still run with Sir Michael Stoute's impressive Hardwicke winner Sea Moon a likely contender.
Brown Panther, Red Cadeaux and Light Heavy are also in the mix.