He resigned his post as stable jockey to Coolmore in November 2010, issuing a statement via his agent to say he had informed Coolmore he wouldn't be renewing his contract. No reason was given but there was speculation that O'Brien was looking for another jockey, and on his recent return from the Breeders Cup at Churchill Downs, where he had ridden four losers for O'Brien, one bookmaker had been offering odds on his replacement. His last Group One winner for the team was Roderic O'Connor in the Criterium International at Saint-Cloud on 31 October 2010.