Trained by Gordon Elliott and ridden by Robbie Power, the 33-1 chance stayed on best of all after The Elbow to hold the late thrust of McKelvey (12-1), with Slim Pickings (331) in third and Philson Run (100-1) fourth.

The 10-year-old won the Welsh Grand National in 2004 when trained by Paul Nicholls and had been antepost favourite for the 2005 renewal of the Aintree spectacular before injury denied him his chance of glory.

However, he made amends for new connections in great style, travelling well throughout as Bewleys Berry, Naunton Brook and Ballycassidy cut out the early running.

He loomed large on the heels of Slim Pickings at the second-last and took a definite advantage after the final fence.

The latter briefly rallied, but it was McKelvey (12-1) who proved the biggest threat, giving his all and just failing by three-quarters of a length.

Power said: "Unbelievable.

What a ride I got the whole way round. He jumped and travelled great.

"Gordon was worried he wouldn't be able to lay-up early on, but it meant I was able to keep out of trouble.

Fair play to Gordon, he has done a top job.

"He jumped out great and I had a look around before we got to the straight and I could see Barry (Geraghty on Slim Pickings) was travelling as well as anything else.

"Once I got to the front he did nothing. Gordon picked him up for nothing (20,000 guineas) and he looks a bargain now."

Elliott said: "We got the horse from the sales and we've tried to sweeten him up by hunting him. He's improved the whole time I've had him and he would have won the last time at Cheltenham but the weight beat him.

"I thought he was better than he was going to Cheltenham and so did Robbie. If he had been in the first five or six we would have been delighted.

"It's been a great team effort. He had a leg injury when we got him, but everything has gone according to plan since."

Jubilant owner Brian Walsh added: "Once he jumped the last in front I knew he wouldn't get caught, there was no chance they were going to get him."

McKelvey ruptured a tendon in his efforts and his trainer Peter Bowen said:

"The horse has broken down, that's why he went across the track. We will just have to see how he is. I've been second in a Gold Cup and second in a National. It's a good feeling, but I prefer winning."

Slim Pickings was reported to be fine, despite not returning to the winner's enclosure.

Nick Williams was understandably delighted with Philson Run's performance and is looking forward to another crack at the race last year.

He said: "I'm thrilled to bits. We thought he could run a good race as the ground was right for him. He will be turned out for the year now and have a light campaign to come back next year."

Fifth home Liberthine was only returned to training after failing to get in foal and she had been covered by 1993 French Derby winner Hernando in the run-up to the race.

She will now return to that stallion as owner Robert Waley-Cohen, father of rider Sam, is keen to breed from his star mare.

Her trainer Nicky Henderson said: "She ran a wonderful race. Horse and jockey enjoyed themselves and she will go back to Hernando next week to get in foal.

"If she doesn't get in foal, we'll have another think."

Graphic Approach, who fell at Becher's Brook on the second circuit, was treated for heat stress.

4.15 Grand National Handicap Chase (Grade 3) (Class 1 ) 4m 4f 6yo plus �399,140 40 runners
1SILVER BIRCH (32) (T) (C, S) G Elliott (IRE) 10 10 6 (Brian Walsh (Co Kildare) R M Power
2 MCKELVEY (21) (P) (F, G, S) P Bowen 8 10 4 (N Elliott) T J O'Brien
3 SLIM PICKINGS (30) (S) T Taaffe (IRE) 8 10 8 (Doubtful Five Syndicate) B J Geraghty
4 PHILSON RUN (56) (G, S) Nick Williams 11 10 5 (Gale Force One) D Jacob