Who is Aidan O’Brien?

Born on October 16, 1969 in County Wexford, Ireland, Aidan O’Brien has, since 1996, has been private trainer to Irish business magnate John Magnier at Ballydoyle Racing Stable, County Tipperary. Magnier is married to Susan O’Brien, daughter of Vincent O’Brien, co-founder of the Coolmore Stud breeding operation in 1975.

Prior to succeeding Vincent O’Brien as ‘Master of Ballydoyle’, Aidan O’Brien had, like his unrelated namesake, been a highly successful National Hunt trainer. In fact, he won Irish National Hunt trainers’ championship in Ireland five seasons running between 1993/94 and 1997/98 and famously trained Istabraq to three consecutive wins in the Champion Hurdle in 1998, 1999 and 2000.

By that stage of his career, O’Brien had already become the youngest-ever winner of the Irish Flat trainers’ championship, in 1997, and was well on his way to becoming the outstanding trainer of his generation. Indeed, he has been Irish champion trainer every year, bar one, since, and British champion trainer on six occasions, most recently in 2017.O’Brien is the leading trainer in the history of the 2,000 Guineas, with 10 wins, including three in a row between 2017 and 2019, courtesy of Churchill, Saxon Warrior and Magna Grecia. He is also, jointly, the leading trainer in the history of the Derby, with 7 wins, most recently with Anthony Van Dyck in 2019. In 2017, O’Brien trained 28 Group One or Grade One winners in a calendar year, thereby beating the previous record, 25, set by the late Bobby Frankel in 2003.