Connections of dual Grand National hero Tiger Roll are hopeful he will make the Boyne Hurdle at Navan in February after undergoing a procedure to remedy a chip in a joint.
The nine-year-old became the first back-to-back winner of the Aintree spectacular since Red Rum when he beat Magic Light by two and three-quarter lengths in April.
Trainer Gordon Elliott has previously stated he is working towards a hat-trick attempt, but Eddie O'Leary, racing manager for Gigginstown House Stud, was reluctant to be drawn on long-term plans before the current issue is resolved.
"It's more than a little bit of a setback, you can't be a little bit pregnant, it's a setback, unfortunately," said O'Leary.
"He's a very sound horse, he exercised on Tuesday perfect and on Wednesday the problem was diagnosed.
"He's being operated on and hopefully they can suck it out.
"He should be back for Navan and the Boyne Hurdle in February after being in his box three or four weeks.
"We just need to get him sound before making plans."
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