In the early summer of 1978, Nishapour, like his predecessor Kalamoun, a grey son of Zeddaan from the Mumtaz Mahal family, defeated Rusticaro by two and a half lengths in the Poule d’Essai des Poulains. In the autumn of 1979 the draft of yearlings sent to Sir Michael Stoute included a still more remarkable member of the family. This was Shergar, a colt by Great Nephew out of Sharmeen. After a twelve-length win in the Chester Vase, a race run on a course that tests ability to handle the Epsom contours, he had rightly become the Derby favourite winning by an astonishing ten lengths.
By now the Irish Derby was not just a consolation prize for the Derby runner-up but rather an opportunity for the Epsom winner to prove himself on a very different circuit. With Lester Piggott standing in for the suspended Swinburn, it was no contest. Shergar had the same winning margin of four lengths at the finish here and in his only encounter with older horses in the King George VI and Queen Elizabeth Stakes at Ascot. His jockey Walter Swinburn, now retired, commented that Shergar was the best racehorse he ever rode.