Not since Nicolaus Silver in 1961 has a grey horse managed to win the Grand National, but Silver By Nature is one of four horses attempting to end this barren spell this year.
Many horses have tried and failed in the last 50 years to become just the third grey winner of the race, although three have gone frustratingly close to Aintree victory in the last 13 years.
Suny Bay chased home Earth Summit under a monumental weight in 1998, What’s Up Boys was collared by Bindaree in the final 100 yards in 2002 and King John’s Castle was no match for Comply Or Die in 2008.
Silver By Nature is the leading fancy of grey-horse backers this year based on his 14/1 price in the Grand National odds and he heads to Aintree on the back of a win at Haydock on his latest start.
Meanwhile, Silver By Nature has also previously finished second in a Welsh National and is well-weighted to run a big race.
Character Building is another of the fancied greys and has valuable experience of the Aintree fences after finishing seventh last year.
That day Character Building was ridden too far off the pace to ever be in contention, but a more prominent ride this year could see him go close at 33/1.
The other two grey entrants are given little pre-race chance in the Grand National betting odds.
Quolibet is priced at 100/1 and has only ever run once outside of France, when pulling up earlier this month at the Cheltenham Festival.
Piraya finished 13th last year and is hoping to improve on this result in The Grand National 2011.
However, he has pulled up on his last two starts this season and is 150/1 in the Aintree betting.
A £20 stake on Silver By Nature winning The Grand National 2011 would return £280. New customers can sign up here to take advantage of free bets totalling up to £60.