Giles Cross was found to be sore when he was pulled up in the Betfred Grand National Trial at Haydock on Saturday.
His trainer Victor Dartnall is having the 11-year-old checked out after jockey Denis O'Regan took him out at the third-last fence in a race he had won 12 months earlier.
"He hit his near-fore joint in the race and is sore. That's why he was pulled up," said Dartnall.
