Colm O’Donoghue will retain the ride on Joshua Tree, the hot Aidan O’Brien-trained prospect for the $6.1 million Japan Cup at Tokyo on Sunday. The confirmation of O’Donoghue as the rider for the Canadian International winner means that Johnny Murtagh has ridden his last race as contract rider for Coolmore. It also suggests that the O’Donoghue could be the Murtagh’s successor at Coolmore, especially as Christophe Soumillon has signed on as first string rider for Ecurie Wildenstein in France.