Tony McCoy will take the ride on Sir Des Champs in the Betfred Cheltenham Gold Cup.
His intended mount Sunnyhillboy was declared a late non-runner by trainer Jonjo O'Neill due to an unsatisfactory scope.
That leaves McCoy free to take over from the injured Davy Russell aboard Willie Mullins' Gold Cup contender.
A tweet from Cheltenham Racecourse read: "Tony McCoy is confirmed to ride Sir Des Champs in today's @BetfredRacing Gold Cup."
The news was also announced on the loud speaker at the track.
