The New One has been ruled out of next month's Grand National meeting due to a spinal issue.
The seven-year-old had been expected to defend his title in the Aintree Hurdle on April 9, but has instead been ruled out for the rest of the season.
Trainer Nigel Twiston-Davies revealed that the horse would not need an operation but will play no further part in the current campaign.
"He's not too bad, but we've stopped him for the season now. He's got a 'kissing spine' but he'll be OK in time. He won't need an operation but we will give him a break," Twiston-Davies is quoted as saying by PA.
The New One finished a disappointing fifth in the Champion Hurdle at Cheltenham earlier this month.
