US Army Ranger to miss Derby The Aidan O'Brien trained US Army Ranger has scoped badly and will not run in the Dubai Duty Free Irish Derby on Saturday. Jockey Ryan Moore who partnered the colt at Epsom will now switch to stablemate Idaho which finished third in the English Classic. Bookmakers have revised their betting on the Irish race by now making Idaho and Harzand joint-favourites at 11/8 despite the fact that Idaho has almost three lengths to make up on his Epsom conqueror.