Bookmakers are cowering at the prospect of an Tony McCoy win
Bookmakers are estimating a £50million pay-out should Shutthefrontdoor land the Crabbie's Grand National and give AP McCoy a dream swansong from the saddle at Aintree.
On his chances of winning, which would lead him to retire on the spot, Ulster legend McCoy said: "That would be a bit of a fairytale and I'm not even sure I'm silly enough to dream that could happen.
"There would be a bit of sadness too, knowing that it would be the last time I'd ever be on a horse."
A bookmakers spokesman said: "An AP victory will not be welcomed by bookies and even though he has been socking it to us for over 20 years, a win on Saturday would be the biggest single loss incurred by the betting industry on one of his winners.
"It's the calm before the storm, we've obviously seen interest in McCoy's horse but there is an ominous feeling.
"The betting clouds are building but it's the biggest race of the year, we won't be running for cover and we'll try and ride out the inevitable onslaught."