Dylan Thomas will lead a powerful nine-strong squad from Aidan O'Brien's yard into the first day of the Ebor festival at York tomorrow where the champion trainer will be triple-handed in the featured Juddmonte International.

As well as Dylan Thomas, O'Brien also pitches the St James's Palace Stakes-runner Duke Of Marmalade and Song Of Hiawatha into a potentially epic clash with the Derby hero Authorized and his old rival Notnowcato after yesterday's final declarations threw up a seven-strong Group One highlight.

Johnny Murtagh will be on Dylan Thomas but Michael Kinane is on board the apparent Ballydoyle number one Mahler in the Ladbrokes Great Voltiguer Stakes in which O'Brien runs four. The race sponsors make the Queens Vase winner a 9 to 4 favourite ahead of Murtagh's mount Yellowstone. Séamus Heffernan will ride Acapulco with Ryan Moore on board Macarthur.

O'Brien runs Septimus in the Group Two Lonsdale Cup and the Galway winner Lucifer Sam will take his chance in the Acomb Stakes.

Tomorrow's intended start to the Tralee festival hangs on a 4.0 inspection this afternoon. The recent weather has left the track unraceable and there was more forecast for last night. However, there is a more positive weather forecast for the week ahead.

Conditions are sure to be testing for this evening's fixture at Roscommon where Murtagh can kick things off successfully on High Court Drama in the juvenile maiden. Murtagh's mount finished runner-up to Belclare on his Curragh debut which looks good enough form for a race of this standard.

Shibina won her maiden at the Curragh in the sort of style that suggests the extra two furlongs of the mile-and-a-half handicap should be ideal. The wide-margin Gowran winner Strike An Ark looks the most likely danger.