Constitution Hill a doubt for Champion Hurdle following disappointing workout at Kempton

Constitution Hill's participation in the Unibet Champion Hurdle is in doubt after the reigning champion had a below-par workout in a pre-Cheltenham visit to Kempton Park.

As has become tradition, Nicky Henderson took several of his Festival contenders for a spin at the Sunbury circuit, including the unbeaten Constitution Hill, whose only start this season was in the Christmas Hurdle at Kempton on St Stephen's Day.

The Seven Barrows trainer said his superstar had since scoped badly.

"Unfortunately, in a routine gallop this morning, Constitution Hill was very disappointing and it transpires, after the vet has scoped him, that there is evidence of mucus," said Henderson.

"We're taking a sample of it to a laboratory to analyse it, which will tell us about the significance of it and we should know more after that.

"Last week, he worked brilliantly and he was scoped 10 days ago, but these things happen, just like it did with him earlier in the year (having to miss Cheltenham on Trials day in January).

"Horses are like humans, look how many people had the awful cough around Christmas that took ages to get rid of."