Connections of Telescope hope he will still run in the English Derby despite having to miss his intended prep race at York on Thursday.
The Galileo colt, owned by Highclere Thoroughbred Racing, was not among the final declarations for the Dante Stakes because of a minor infection which developed in grazes on two of his legs.
The setback occurred when he was was being loaded onto a horsebox, but the premier Classic at Epsom on June 1 remains the objective.
Instead of a race, trainer Sir Michael Stoute plans to give him a racecourse gallop as part of his preparation.
“It’s obviously very disappointing, particularly for all of his owners, that Telescope cannot run in the Dante on Thursday,” said Highclere managing director Harry Herbert.
“Sir Michael couldn’t give Telescope anti-inflammatories as it was too close to the Dante and unfortunately we have discovered through a blood test that the grazes have become infected.
“We are hoping that Telescope will still make it to the Derby and Sir Michael is hoping to give him a racecourse gallop in preparation.”
Telescope went into winter quarters as a leading fancy for Classic honours on the back of a maiden win at Newmarket in September.
His only other start as a juvenile came when a promising second to Snow King on debut at Ascot earlier that month.
Telescope’s syndicate of owners include retiring Manchester United manager Sir Alex Ferguson.
Another of Highclere’s syndicates will be represented in the Dante by Greatwood, who was a late withdrawal from Saturday’s Lingfield Derby Trial because of the rain-softened ground.
