Dermot Weld felt the fast ground at Newbury was responsible for Grey Swallow's poor showing in the King George VI And Queen Elizabeth Diamond Stakes on Saturday.
The son of Daylami, who won the Budweiser Irish Derby last season, looked ill at ease throughout Saturday's Group One contest and finished seventh place behind outstanding winner Azamour.
"The ground was very fast, as we saw with two track records being set," said Weld. "The winner's performance was brilliant, but our horse just never let himself down on the ground."
"I said all along week that the fast ground was a concern and so it proved. We will see how he comes out of the race before making plans for the autumn."
Weld is planning an autumn campaign for Grey Swallow, with possible races in the US & Europe a target.
