DUBLIN (AFP) - Irish trainer Aidan O'Brien hopes his all-conquering Duke of Marmalade lands the Irish Champion Stakes at Leopardstown on Saturday.

The four-year-old colt has won five Group Ones already - O'Brien has won 18 in all and is bidding to break the world record of 26 in a season - and provided the ground holds up his horse will take on Epsom Derby winner New Approach.

It will be the second time in three weeks that the two will have clashed following the 'Duke's' impressive victory in the Juddmonte International Stakes where New Approach finished third.

That race aroused some controversy with O'Brien and Colm O'Donoghue - rider of the pacemaker Red Rock Canyon - being called to a disciplinary hearing over a possible breach of team tactics employed during the race at Newmarket.

However, the rematch between the two Irish equine stars promises to be a cracker with the other seven runners playing supporting roles at best.

The punters seemed to drift away from Duke of Marmalade earlier in the week as they piled large sums on the Jim Bolger-trained New Approach, but the former should still start odds-on favourite on the day.

Duke's jockey Johnny Murtagh said it was a privilege to have the opportunity to ride such a horse.

"I am a very lucky jockey - it's very easy to ride a horse of his calibre, with his balance and physique," commented Murtagh, who has enjoyed a resurgence in his career after battling alcoholism.

"Duke is a very durable, consistent horse with a great will to win on both soft and firm ground."

New Approach's third in Newmarket could be put down to having had a lay-off with an injury and should be better for the run.

If he reproduces the form that saw him finish second twice to O'Brien's other multiple Group One winner Henrythenavigator in the English and Irish 2000 Guineas then the Duke will have a real battle on his hands.