Bookmakers slashed the Derby odds yesterday against Cairdeas, who runs in the colours of the President of Ireland, Mary McAleese. The colt's price tumbled from 33-1 in the morning to less than half those odds by late afternoon.

Cairdeas runs in the Gallinule Stakes at the Curragh this Sunday as part of his preparation for Epsom on 5 June. Ridden by his usual jockey, Pat Smullen, he won by four lengths at Naas two weeks ago.

''We were knocked over for the 33-1, cut him to 20-1, but shrewd punters kept backing him at that price including one bet of £1,000 each-way," said Simon Clare, a spokesman for Coral. "He is now 14-1. We'll find out how informed the gamble was when Cairdeas runs on Sunday."

Cairdeas was bred by the state-run Irish National Stud and is trained by Dermot Weld. A son of Darshaan, there is abundant stamina in his pedigree for the 12-furlongs of the Derby. Weld has warned of one weakness in the colt's make-up - he would hate firm ground.

Percussionist, who occupies a similar position in the Epsom betting, is likely to be ridden by Kevin Darley, the colt's trainer, John Gosden, indicated yesterday.

Darley, a former champion jockey, is expected to come in for the ride because of Frankie Dettori's commitments to Godolphin. Dettori, who is due to ride the well-backed second-favourite Snow Ridge in the big race, rode Percussionist on his latest start, a 10-length victory in the Lingfield Derby Trial earlier this month.

In the Oaks, on 4 June, the Godolphin contenders Sundrop and Punctilious head the list of 21 fillies who stood their ground at yesterday's forfeit stage. Sundrop was beaten only half a length by all-the-way winner Attraction in the 1,000 Guineas to earn her position at the head of the betting for the Epsom Classic. Punctilious was impressive when making all to win the Musidora Stakes at York last week by six lengths.

Their trainer, Saeed bin Suroor, said yesterday: "Sundrop worked today over a mile with New South Wales and I'm very pleased with her. Punctilious also worked over seven furlongs with Opera Comique and it is so far so good with both of them. Soon we will decide which one will be ridden by Frankie [Dettori] and which one by Kerrin [McEvoy]."

Ouija Board won the Pretty Polly Stakes at Newmarket, and her odds for Epsom are shortening now that Kieren Fallon has been booked.

Hathrah, a creditable third in the 1,000 Guineas, only half a length behind Sundrop, is another intended runner. Her trainer, John Dunlop, said: "Hathrah has done very well since her run in the Guineas and it is definitely the plan to run her in the Vodafone Oaks. My only reservation is that she would not want the ground too fast, good would be acceptable but good to soft would be even better."

DERBY ODDS (Coral): 5-2 Yeats, 7-2 Snow Ridge, 9-2 North Light, 10-1 American Post, 12-1 Salford City, 14-1 Cairdeas, Azamour, Rule Of Law, Let The Lion Roar, 16-1 Ecomium,

Percussionist, Grey Swallow, 20-1 Bull Run, 25-1 Meath, 33-1 Book Of Kings, Duke Of Venice, Moscow Ballet, 50-1 Pukka, Almuraad, Elshadi, 66-1 Massif Centrale, Moncreiff, Return In Style, 80-1 Coming Again, 100-1 Shaaban.

OAKS ODDS (Ladbrokes): 11-4 Sundrop, 5-1 Punctilious, 6-1 All Too Beautiful, Ouija Board, 12-1 Baraka, Hathrah, 16-1 Poise, 20-1 Necklace, 25-1 Alexander Goldrun, Green Swallow, 33-1 Australie, Bowstring, Lisieux Orchid, Tamarillo, Kisses For Me, 40-1 Anna Pallida, Crystal, Kinnaird, Menhoubah, Si Si Amiga, 50-1 Last Love.

RICHARD EDMONDSON

Nap: Silent Hawk

(Newmarket 4.55)

NB: Strike

(Haydock 4.45)