Willie Mullins has warned Irish runners may be hindered by a change to the fences at the Cheltenham Festival.
The top Irish trainer believes the travelling team will have to consider that they now have a white-coloured trim.
Orange at the big meeting in March 2022, Mullins felt reigning champion chaser Energumene was affected by the difference on Saturday.
The 4-9 favourite was no match for Editeur De Gite in the Grade 1 Albert Bartlett Clarence House Chase, his warm-up for his double title bid.
Assessing the shock defeat, Mullins said: "It was his first time going to England and jumping the new white fences, even though he had jumped them at home, and he just baulked at the first.
“It was definitely a useful exercise for us and I’d say it’s something a lot of Irish horses are going to have to prepare for because if you miss the first at Cheltenham, your race could be gone.”
The transformation of the fences as well as hurdles, gradually phased in by the British Horseracing Authority since March last year, is a welfare-driven project.
A study by Exeter University found that horses could see white better and improved their jumping if the wood and vinyl padding of take-off boards, guard rails and the trim was white.
But 20-times champion jockey Sir AP McCoy and ITV Racing pundit called it 'rubbish', based on his experience of race-riding
"I think it's the biggest load of rubbish," he said. "Do they honestly think it's going to stop horses from falling? There have still been plenty of fallers over them. I don't think horses jump any better or any worse over them.
"I don't know what scientist came up with the idea they think the horses can see them better."
Ruby Walsh said: "I jumped white in France, orange in England or Ireland, and I don't the colour ever made that much difference to tell you the truth."
Energumene. who runs in the colours of Brighton owner Tony Bloom, suffered only his second defeat in ten starts over fences which cost one high rolling punter £725,000 in lost bets after staking £350,000 at odds of 4-7 and £375,000 at 8-15 with Star Sports on the Mullins star to win.
