Davy Russell will miss the ride aboard Sir Des Champs in the Betfred Cheltenham Gold Cup after suffering a punctured lung.
The rider took a crashing fall from Un Beau Matin at the final flight in Wednesday's Coral Cup but was fit enough to take up his first two mounts on Thursday's card.
However, after finishing unplaced on both Argocat in the Jewson Novices' Chase and Stonemaster in the Pertemps Final, Russell was ruled out for the rest of the meeting.
The jockey has ridden Sir Des Champs on his last six outings, including his Irish Hennessy win.
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