Maurice Linehan is likely to be sidelined for at least a couple of months after suffering injuries in a fall at Kempton.
The 5lb claiming conditional has been detained in St George's Hospital, Tooting, following his spill from the Jonjo O'Neill-trained Mister Hyde at the first fence in the Racing Plus Chase.
"He's broken his sternum and has broken two vertebrae," said the Jackdaws Castle handler.
"He's still in hospital for a few days and we will see what happens when it all settles down a bit. He'll be out for a little while.
"I'm no doctor, but from experience I'd say he'd be out for a couple of months."