Border Arrow is lame and out of today's £250,000 Prince of Wales's Stakes at Royal Ascot.
The five-year-old, placed in the 2000 Guineas and Derby in 1998, was to take on superstars Dubai Millennium and Sendawar in the Group One showpiece over 10 furlongs.
Trainer Ian Balding said this morning: "He was cast overnight we think and he's lame behind this morning sadly."
Plans for the son of Selkirk, who was third to Daliapour in the Coronation Cup at Epsom on his latest start, have now been put on hold.
"We'll have to wait and see how he is," he added.
With the Clive Brittain-trained Pegnitz also out of the contest, only six horses will go to post for the feature race on day two of the Royal meeting.
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