The six-year-old required veterinary treatment at the Berkshire track after returning lame following his second successive win in the Group Two contest on Saturday.
Although the full extent of his injury has still to be revealed, connections have announced the William Haggas-trained son of Sea The Stars faces a lengthy spell on the sidelines.
Angus Gold, racing manager to owner Sheikh Hamdan Al Maktoum, said: "We are still waiting the full extent of the damage, as we have not been able to scan it properly yet.
"It is ligament damage and he will definitely be out for the rest of this year. Unfortunately I can't say exactly what he has done until we know the full extent of the damage.
"I spoke to William last night and he was waiting to get a vet's report. He has never missed a day in his life and is as sound as you can get, but this is what happens to horses sometimes.
"They did a great job at Ascot and the main thing is that he is still with us. He will be standing in his box for a couple of months at least."