o'neill hosted a media stable visit on thursday at his jackdaws castle yard in gloucestershire and said he could not be happier with favourite for the crabbie 's grand national , shutthefrontdoor .
he trains shutthefrontdoor for his principal patron j p mcmanus , who owns jackdaws castle and retains ap mccoy , the record-breaking jump jockey who is about to gain his 20th consecutive jockeys ' championship and retire that mccoy has not decided yet whether he is riding shutthefrontdoor in the £ 1million crabbie 's grand national at aintree on april 11 .