Sam Waley-Cohen is optimistic that the fences won’t prove a barrier to Long Run’s bid for glory in the Crabbie’s Grand National at Aintree today.

Much has been made of the 2011 Cheltenham Gold Cup hero’s tendency to make the occasional jumping error.

But amateur rider Waley-Cohen is quick to defend the nine-year-old gelding, owned by his father, Robert, who lives at Edgehill, near Banbury.

“I can’t wait to ride him,” said the former pupil of the Dragon and St Edward’s schools in Oxford.

“People make a lot of his jumping and say he is not a good jumper. I don’t think that is accurate. I think he is a good jumper.”

However, he admits that if the fences hadn’t been modified they wouldn’t have considered a crack at the race with Long Run.

“No we wouldn't have,” added the 31-year-old . “I think there is truth to that.

“We hope he completely changes the way he jumps around the Grand National fences and I think there is good reason to believe he will.

“With the National fences you would hope they would make him back off and make him think about the fences and respect them.”

Long Run, a best-priced 12-1 second favourite for the National, bounced back to winning form when dropped in class at Kelso last month, having unshipped Waley-Cohen at the last fence when beaten in his attempt for a third King George VI Chase crown at Kempton.

“It was just very pleasing the way he galloped away from Knockara Beau,” added Sam, who enjoyed the perfect boost ahead of today when recording his fourth win over the big fences with victory on Warne in the Fox Hunters’ Chase on Thursday.

It added to his two previous wins in the race on Katarino (2005 and 2006) and his success on Liberthine in the 2006 Topham Chase.

It will be Waley-Cohen’s fifth ride in the Aintree marathon, having finished second and fourth on Oscar Time and fifth on Liberthine, who was trained, like Long Run by Nicky Henderson, at Lambourn.

“It’s a race that has been very kind to me and as Long Run has had such an impact on the life of everybody in our family, it would be amazing if he could win it,” said Waley-Cohen. “It’s the greatest race in racing.”

Robert Waley-Cohen added: “I still get a tingle ahead of the National as it’s a great race.

“Clearly Long Run has deteriorated since his days of beating Kauto Star and Denman in the Gold Cup, but he has been handicapped accordingly.

“All you can wish for is a clear run and then take it from there.”