Saffron Walden will be the sole Aidan O'Brien trained horse in Saturday's Vodafone Epsom Derby.
Tchaikovsky and Urban Ocean had been regarded as other possible Derby runners, but Tchaikovsky is now more likely to line up for Sunday's Prix du Jockey Club at Chantilly.
The Cork winner, Urban Ocean, will have any graduation to Group One level postponed until after Friday evening's Gallinule Stakes at the Curragh, and another Ballydoyle colt, High King, is set to wait for Royal Ascot's King Edward VII Stakes.
"At this stage Saffron Walden looks like he will be our only runner at Epsom," O'Brien confirmed as 34 horses were left in Europe's most prestigious classic.
Saffron Walden remains at the forefront of the Derby betting, thanks partly to the public support from the Essex town after which he is named. The Jockey Club agreed to have the colt's name corrected last Friday after he won the Irish 2,000 Guineas under the name Saffron Waldon.
Port Bayou has been forced to miss Saturday's Belmont Stakes in New York due to muscle problems and will now be trained for the Irish Derby.
"He is fine now after being cast in his box, but it was just too late," said Dermot Weld's son Mark yesterday.
"The three days off cost him. Please God he can be placed in the Irish Derby and there are lots of races for him later in the year in America." he added.
