Leading contender Brown Panther has been ruled out of Sunday's GAIN Irish St Leger at the Curragh.
Joint-owned and bred by Michael Owen and trained by Tom Dascombe, the five-year-old was a close third in the Group One contest 12 months ago and was being geared towards this event and then the Emirates Melbourne Cup.
However, he spiked a temperature on Thursday and having failed to eat anything during the entire day, Dascombe has had no choice but to rule his Goodwood Cup hero out of a trip to Ireland this weekend.
Dascombe said: "Unfortunately, he won't be running on Sunday.
"We've had him out for a canter this morning and he seems fine, but he didn't eat for some reason and we can't take any chances.
"It's disappointing, but these things happen. Things could be worse, we've still got a horse left and we'll just have to see how long it takes him to recover and aim for something else.
"He's in the Qipco staying race at Ascot on Champions Day (Qipco British Champions Long Distance Cup, 19 October) and the Melbourne Cup and both are still options for him.
"If he is going to go to Australia, he doesn't have to go into quarantine until 26 September, so we've got a few days for him to recover."
Royal Diamond is among the 11 runners to line up this Sunday, following this morning’s declaration of runners.
The Johnny Murtagh trained and ridden performer will attempt to become only the fifth horse to win back to back Irish St Legers having won the race 12 months ago.
Dubai Duty Free Irish Derby runner up Galileo Rock has also been declared for the Group One Classic but also holds an entry in the English equivalent and a decision will be made later today.
Trainer Aidan O’Brien will be represented by Ernest Hemingway and Chamonix.
Dermot Weld, who has won the race with both Vinnie Roe and Vintage Crop, has both Pale Mimosa and Voleuse De Coeurs, while John Oxx will run Saddler’s Rock.
The strong British trained challenge featured the Godolphin owned Ahzeemah and the much travelled Red Cadeaux trained by Ed Dunlop.
Aidan O’Brien has landed the Group One Goffs Vincent O’Brien National Stakes on eight occasions and the master of Ballydoyle has a strong representation this time around with Friendship, Giovanni Boldini and Wiltshire Boulevard .