Leading sire Danehill has died after sustaining a freak injury at Coolmore Stud Co Tipperary.
The 17-year-old was being hand-grazed in a paddock at the time of the incident.
Danehill, the sire of last season's brilliant miler Rock Of Gibraltar, was responsible for both Clodovil and Catcher In The Rye, who were first and second respectively in last Sunday's French 2000 Guineas.
Danehill was the leading sire of Pattern-race winners in Europe last year with 13 winners of 24 races, knocking another Coolmore inmate, Sadler's Wells, off top spot after a reign of six consecutive years.
The most prolific of his winners was Rock Of Gibraltar, who won five times at Group One level in the colours of Manchester United manager Alex Ferguson.
Danehill was a stud phenomenon in Australia before he achieved star status in Europe, siring top-class horses from the start of his shuttle career in New South Wales.
He had a season in Japan in 1996, but on his return to Coolmore began to produce results in Europe just as outstanding as those on the other side of the world.
He was even better at stud than on the racetrack, where he won four of his nine races including a Group One victory in the Sprint Cup at Haydock Park. He was also third behind Nashwan in the 2000 Guineas.