St Nicholas Abbey, the Classic flop who became the winner of six Group One races and the highest-earning runner in the history of Ballydoyle, lost his battle with chronic health problems when he had to be put down after an attack of colic.
Unbeaten in three starts at two, the son of Montjeu started as evens favourite for the 2,000 Guineas in 2010 but finished only sixth. Injury ruled him out of the Derby and he did not return until the spring of 2011. Best racing left-handed, he scored top-level wins at the Breeders' Cup and in Dubai, as well as a hat-trick of Coronation Cups at Epsom, for a total of £4,954,590 in prize money.
A fractured pastern ended his career last July and, despite progress from major setbacks with colic and laminitis, an inoperable attack of colic meant he could not be saved.