Keith Desormeaux was doing the work. The 2-year-olds Texas Red and Danette were cooled out in their stalls while Marchman, the barn’s older pro, was getting his bath after a work on the grass. Wearing a morning growth of whiskers and a gray T-shirt flecked with sweat and straw, Desormeaux, 47, moved among them, letting himself feel a little bit of the excitement of the approaching Breeders’ Cup.