 In 1855 he won the Cambridgeshire Handicap with Sultan and in the following year he added a second Chester Cup with One Act.Four years later, Day won a second classic when he trained his own horse, The Promised Land, to win the 2000 Guineas, ridden by his younger brother Alfred.In 1860, Day's horses completed the Newmarket "Autumn Double" when Dulcibella won the Cesarewitch Handicap and Weatherbound won the Cambridgeshire, with Dulcibella's win reportedly resulting in Day taking £60,000 in successful bets.