Sir Percy (foaled 2003) is a British Thoroughbred race horse and sire. In a career which lasted from July 2005 to June 2007 he ran ten times and won five races. he was among the leading British two-year-olds of 2005, when his win included the Dewhurst Stakes. In the following year he recorded his most important success when winning The Derby. He was retired to stud after three unsuccessful starts in 2007. Background Sir Percy was bred by Harry Ormesher at the Old Suffolk Stud in Hundon, Suffolk. His sire Mark of Esteem won the 1996 2,000 Guineas; his dam Percy's Lass won the Group 3 September Stakes in 1988 (and subsequently died of colic when Sir Percy was a foal. Sir Percy was the last of her offspring) and his damsire Blakeney won the Epsom Derby himself in 1969. Sir Percy was named after Sir Percy Blakeney, the hero of the novel The Scarlet Pimpernel. In November 2003 Sir Percy was sent as a weanling to the Tattersalls sales. He was bought for 20,000 guineas by Will Edmeades bloodstock, acting on behalf of Anthony Pakenham. Pakenham bought the colt as compensation for losing a National Hunt Horse. Sir Percy was sent into training with Marcus Tregoning at Lambourn, Berkshire. He was ridden in all his races by Martin Dwyer. Racing career 2005: two-year-old season Sir Percy was undefeated as a two-year-old, winning all four of his races. He made his debut in a maiden race at Goodwood on 28 May. He started at odds of 8/1 and finished strongly to win by one and three quarter lengths. Four weeks late he started 7/4 favourite for a minor stakes race at Salisbury and won by one and a quarter lengths from . On 27 July Sir Percy completed his hat trick and recorded his first Group race success when beating Cool Creek by a neck in the Vintage Stakes at Goodwood. Sir Percy was then rested until returning in Britain's most prestigious two-year-old race, the Dewhurst Stakes, on 15 October. He was held up in the early stages before producing a powerful late run to take the lead inside the final furlong and win by a neck from the odds-onn favourite Horatio Nelson. 2006: three-year-old season Sir Percy made his seasonal debut in the 2000 Guineas on 6 May. He started 4/1 second favourite in a field of fourteen runners.