Runaway winner of the Ballysax Stakes and Derrinstown Stud Derby Trial, the grey was added to the field for the Epsom Classic at a cost of £75,000 but finished last of the 12 runners.
Condon reported his charge had come back sore in the immediate aftermath, and further examinations revealed the injury blow.
Condon said: “He pulled up sore on Derby day, we carried out further investigations on Monday and Tuesday and an X-ray has revealed he sustained a stress fracture to a near-fore limb.”
Condon is, however, hopeful the son of Jeremy, who has won four of his seven starts, will be back later in the year.
He added: “He’ll have another X-ray next Monday and the prognosis is good, hopefully we will still have him back for an autumn campaign.”
Meanwhilke Investec Derby hero Golden Horn is among 31 entries for the King George VI And Queen Elizabeth Stakes at Ascot on July 25.
The John Gosden-trained colt ran out an impressive winner of the premier Classic at Epsom and could take on his elders in the midsummer showpiece sponsored by Qipco, a path used by Taghrooda from the same stable following her Oaks success 12 months ago.
He is expected to take in the Coral-Eclipse over a mile and a quarter for his next race at Sandown three weeks earlier.
Gosden has four other King George possibles in Derby runner-up Jack Hobbs, Eagle Top, Romsdal and the unexposed Mahsoob.
Michael Stoute, who has five King George wins, has two entries in Hillstar and Telescope. Telescope, runner-up to Taghrooda in 2014, is set to run first in the Hardwicke Stakes at Royal Ascot on Saturday week following his facile win at Newbury last month.
Harry Herbert, racing manager for owners Highclere Thoroughbred Racing, said: “Everything is going really well with Telescope and Sir Michael is very pleased with the way he came out of the Newbury race.
“His next target was always going to be the Hardwicke Stakes at Royal Ascot and touch wood that is where he will be running next week. The King George will also definitely come into play.”
Three-times King George winner Aidan O’Brien is responsible for nine of the 10 Irish-trained entries.
They include the shock 50-1 Investec Oaks winner Qualify, Derby fourth Giovanni Canaletto and French Derby runner-up Highland Reel, plus the highly-rated John F Kennedy and Ol’ Man River who have yet to hit form this year.
The other Irish possible is last year’s Champion Stakes third Free Eagle from Dermot Weld’s stable.
Other leading contenders from the home team include The Grey Gatsby, Coronation Cup scorer Pether’s Moon and Just The Judge.
The French contingent looks strong with French Derby victor New Bay and Dubai Sheema Classic heroine Dolniya in the list.
Novellist gave Andreas Wohler the biggest success of his career in this race two years ago and the German trainer has put in Karpino, the impressive winner of the German 2000 Guineas.
Trainer Stefano Botti is responsible for both Italian entries, dual Group One winner Dylan Mouth and Celticus, his regular pacemaker.
- Cirrus Des Aigles will miss the Grand Prix de Saint-Cloud later this month after suffering a minor setback.
Corine Barande-Barbe’s stable star was due to clash with dual Prix de l’Arc de Triomphe winner Treve in the June 28 feature, but the nine-year-old is now set for a spell on the easy list.
Barande-Barbe said: “It’s just a little problem with his leg, it’s very, very small but it just means that we cannot work him at the moment.
“It’s nothing serious, just a little bump and a bruise but it will prevent him from running in the Grand Prix de Saint-Cloud.
“With a horse like him who gives everything in his work and racing, you have to be sure everything is 100 per cent otherwise you can have serious problems.