The Charlie Appleby-trained Hamada hasbeen euthanised after fracturing a hind leg in a routine track gallop at Werribee.
Hamada was in Australia preparing for the Melbourne Cup for which he was considered one of Godolphin's leading contenders for the famous 3200m race at Flemington next month.
In a Twitter post from global racing operation Godolphin on Saturday, Appleby said it was a freak accident.
"On vet's advice, the nature of the injury left us no alternative. The kindest course of action was to euthanise the horse," Appleby said.
Hamada won five of his seven starts.
The Appleby stable had runners at Caulfield on Saturday including Blair House who was narrowly beaten by another Godolphin international visitor, the Saeed Bin Suroor-trained Benbatl in the Group One Caulfield Stakes.