It was mooted after his thrilling victory in this year's Aintree Grand National that Rule The World would shortly be retired.
On Tuesday, that came to pass when it was announced that the first novice to win the jumping highlight would be seen no more on the race track.
Having twice fractured his pelvis in his younger days, connections felt it would be asking too much of the horse to continue under big weights in handicaps having proved he was not quite up to Grade One level.
Commenting on the decision to retire the nine-year-old, trainer Mouse Morris told RTÉ Sport: The lads (Gigginstown Stud) have come to a decision and I think it's the right one. He's well and he's healthy, so he can enjoy himself for the rest of his life."
When asked whether it was a difficult decision, the Co Tipperary handler added: "It probably was. He's only nine but where do you go after winning the greatest National Hunt race in the world?
"He's going out at the top and can now join the Gold Cup winner War Of Attrition."