A statement from the stable said that Spencer had resigned from his position, but his departure, after a pretty disastrous year, had long been expected.
Richard Henry, a spokesman for the breeding wing of Magnier's empire, Coolmore Stud, said last night: "Jamie is a young jockey with a lot of talent and has a long career ahead of him. All the team at Ballydoyle wish him the very best."
They were typically generous words from the team on the departure of one of their key members. Just a year previously they had been similarly magnanimous when Michael Kinane exited the hot-saddle seat to make way for Spencer.
Now, the possibility is that Kinane's failures could be reviewed with a softer focus and he could be welcomed back into the fold. However, John Murtagh, who has ridden many top-flight winners for O'Brien and whose stint in Britain last season as stable jockey to David Loder was not a success, is the bookmakers' favourite to take over the job. Kieren Fallon and Darryll Holland are also quoted in Paddy Power's betting.
Spencer's year in the job was punctuated by criticism as he picked up several early-season suspensions and, like so many European riders, failed spectacularly on the biggest stage of all at the Breeders' Cup meeting. Spencer was criticised for committing too early on Powerscourt in the Turf and for a weak finish on Antonius Pius when second in the Mile. Powerscourt had also suffered disqualification when finishing first in the Arlington Million. The American press were not sympathetic.
Nevertheless, Spencer ended the year as Ireland's champion jockey at the age of just 24 and produced the goods on late-season Group One winners Ad Valorem and Oratorio, who will lead the Ballydoyle Classic team this year.
Overall, though, it was another very poor year for O'Brien at the highest level and Spencer's job was made a good deal harder by the failures of the stable's flagships, particularly the hot favourite for the 2,000 Guineas, One Cool Cat.
Paddy Power make Murtagh 4-6 favourite in their book on who will be the next No 1 rider at Ballydoyle. Fallon and Holland are both on 3-1. Ladbrokes make Murtagh 8-11 to be Irish champion jockey, with Michael Kinane a 3- 1 chance and Kieren Fallon available at 5-1.Reuse content