Born on May 23, 1993, Joseph O’Brien is the elder son of Ballydoyle legend Aidan O’Brien and first rose to prominence as a Flat jockey, riding predominantly for his father, between 2009 and 2015. O’Brien Jnr. rode his first winner, Johann Zoffany – subsequently transferred to Australia and renamed ‘Muir’ – at Leopardstown on May 28, 2009, just five days after his sixteenth birthday.
However, granted that he stands 5’11” tall, 9″ taller than an average Flat jockey in the British Isles, Joseph O’Brien was always destined to fight a losing battle against the scales. Nevertheless, in his truncated six-and-a-half-year career in the saddle, he still managed to ride a total of 518 winners, including no fewer than 31 Group 1 winners worldwide. He was Irish champion apprentice twice, sharing the title with Gary Carroll and Ben Curtis in 2010 before winning it outright in 2011, and Irish champion jockey twice, in 2012 and 2013.
In March, 2016, O’Brien told the ‘Racing Post’ that he would no longer be riding and would concentrate, instead, on his new career as a trainer. He was officially granted a training licence in June, 2016, at which point he formally took charge of the family training establishment on Owning Hill, near Piltown, Co. Kilkenny, previously occupied by his father, his mother, Anne-Marie, and his maternal grandfather, Joe Crowley. He saddled his first winner as a trainer, Justice Frederick, ridden by his younger brother, Donnacha, at Gowran Park on June 16, 2016, and wasted little time in opening account at the highest level. On September 11, 2016, his two-year-old filly Intricately, also ridden by Donnacha O’Brien, belied odds of 25/1 to win the Moyglare Stud Stakes at the Curragh, by a short head from Hydrangea, trained by his father.