Small in stature, but a colossus of equine class and courage, Tiger Roll is developing into the horse of a generation. An animal with an awe-inducing engine who, on a Saturday afternoon in April, had trainer Gordon Elliott, jockey Davy Russell and owner Michael O’Leary questioning the depth of their good fortune. He didn’t just win the Grand National. He turned it into a procession. Russell barely budged for the first four miles before engaging top gear after the last and the little horse with the big heart duly rolled into the history books, the first since Red Rum in 1974 to win back-to-back Nationals.