Chaparral heads Ballydoyle Derby team Aidan O`Brien is set to run four in the Budweiser Irish Derby at the Curragh on Sunday.Heading the Ballydoyle trainer`s quartet will be Vodafone Derby hero High Chaparral, who bids to follow up his Epsom Classic success in the Irish version as his former stable companion Galileo did last year.He will be one of the shortest-ever favourites for the race with Paddy Power quoting him at 2-9.Accompanying High Chaparral will be Italian Derby runner-up Ballingarry, Della Francesca and either Roar Of The Tiger or Sholokov.O`Brien was responsible for six of the 11 horses standing their ground at today`s five-day declaration stage.His other entry is Hawk Wing, but the runner-up in both the Sagitta 2000 Guineas and the Vodafone Derby to stablemates Rock Of Gibraltar and High Chaparral respectively, has only been left in as a precaution.'We always do this. We leave the main horses in until the final declaration day,' O`Brien said this afternoon.'Hawk Wing is being trained for the Eclipse at Sandown the following weekend.'Hawk Wing and High Chaparral are both well, they are working nicely and seem fine.'O`Brien`s jockey plans for the Irish Derby will not be finalised until later in the week.But he confirmed that Rock Of Gibraltar`s attempt at a sixth successive Group One victory would be in the Sussex Stakes at Glorious Goodwood following his impressive win in the St James`s Palace Stakes at Royal Ascot last week.Two other Irish-trained colts and three horses from England make up the Irish Derby 11.Dermot Weld is double-handed with In Time`s Eye, who was runner-up to High Chaparral in the Derrinstown Stud Derby Trial at Leopardstown on his latest start and Jazz Beat.Balakheri, winner of the King Edward VII Stakes at Royal Ascot last Friday, is one of two horses left in by Sir Michael Stoute.The Newmarket trainer, who has won the Irish Derby three times with Shergar (1981), Shareef Dancer (1983) and Shahrastani (1986), could also run Princely Venture.Completing the field is Nysaean, trained by Richard Hannon.There is no French-trained representative as Prix du Jockey Club runner-up Act One has been retired after sustaining a leg injury.Paddy Power bet: 2-9 High Chaparral, 6-1 Balakheri, In Time`s Eye, 16-1 Ballingarry, 20-1 Nysaean, 25-1 Della Francesca, Princely Venture, 40-1 Jazz Beat, Sholokhov, 50-1 Roar Of The Tiger.