Sizing Europe has been ruled out of the King George VI Chase at Kempton because of the rain-softened ground.
The former champion chaser was fourth favourite for the Boxing Day race.
He is set to run at Leopardstown instead, probably in the Paddy Power Dial-A-Bet Chase on 27 December, with the longer Lexus Chase an alternative option a day later.
Another Irish-trained horse ruled out of the King George is First Lieutenant, who will line up for the Lexus.
But Somerset trainer David Pipe says he has supplemented his Cheltenham Festival and Royal Ascot winner Junior for the Kempton race.
Former winner Long Run is the King George favourite ahead of Cue Card and Riverside Theatre.
Sizing Europe won the 2011 Queen Mother Champion Chase and was runner-up a year later in the race over two miles at the Cheltenham Festival.
Trainer Henry De Bromhead said he would be keen to step him up to three miles on good ground.
"He has the two options at Leopardstown and we'll leave him in both races , but the way the weather is going at the moment, I would imagine he'll probably run in the two-mile race," he said.