Telecaster and Sir Dragonet have been added to the field for the Investec Derby at Epsom on Saturday.
Hughie Morrison's Telecaster lowered Too Darn Hot's colours in the Dante Stakes at York, while the Aidan O'Brien-trained Sir Dragonet was a spectacular winner of the Chester Vase.
East Ilsley-based Morrison said that ultimately it was a "relatively easy decision" to add the New Approach colt to the field, at a cost of £85,000 - but that the anxious part now begins.
Morrison said: "Based on the fact we've had no issues and he's been in good form since the Dante, it was a relatively easy decision.
"The difficult part starts now, really - the next five days. By rights we should be waiting until Thursday to make a final decision, but we don't envisage any problems and if there were any doubts we wouldn't have done it.
"We've done it because it is the Derby. It is the responsibility of all of us to ensure that the Derby remains just that - the turf race of the season.
"Whatever happens on the day, it would be a lesser race if he wasn't there."
He added: "I can't really look forward to it now and I'll have five sleepless nights if I'm honest, worried that the horse might do something.
"He could stand on a stone or anything, it happens daily in every yard, so we'll all be a bit nervous."
O'Brien has a formidable party of eight, also being able to call on Anthony Van Dyck, Broome, Cape Of Good Hope, Circus Maximus, Japan, Norway and Sovereign among the 15 that remain in the mile-and-a-half showpiece.
Kevin Prendergast's Madhmoon, fourth in the 2000 Guineas at Newmarket, is the other Irish-trained possible.
As well as Telecaster, the home team is also represented by the Andrew Balding-trained Bangkok, John Gosden's Humanitarian, Charlie Appleby's Line Of Duty, Roger Varian's Surfman and the John Ryan-trained Hiroshima.