Cheltenham legend Altior is a big doubt for the Queen Mother Champion Chase after being found lame on Sunday morning.
The ten-year-old has won the last two Queen Mother Champion Chases at Cheltenham and was fancied to make in three in a row.
However, a problem was discovered on Sunday morning with an old splint that had been dormant.
It means Altior may have to miss out on Cheltenham this year and lost out on his chance to win his fifth race at the Festival.
Trainer Nicky Henderson says they are trying to do everything they can to make sure he is fit to run on Wednesday, where he will be up against the likes of Defi Du Seuil and Chacun Pour Soi should he make it.
However, he accepts it will be tricky to get him back fit.
“Unfortunately Altior was lame this morning, due to an old splint that has been dormant. It's never bothered him before and typically it rears its ugly head now,” said Henderson.
“We are working away and there's lots we can do, we have two days, but it's an uphill battle. We have the treadmill he can go on and it's very cold water, which helps these things a lot.
“We have to keep going. We're working away and we'll either get lucky or we won't.”
