Tartan Snow, a 100-1 chance, edged out Cool Friend in a thrilling finish to the John Smith's Fox Hunters' Chase on the opening afternoon of the Grand National meeting at Aintree.
Cool Friend looked like landing the amateur riders' Grand National when he led over the final fence, but he could not quite shake off the opposition.
Jamie Hamilton brought Stuart Coltherd's 13-year-old with a late charge to snatch victory in the last few strides.
Coltherd said: "It's unbelievable. We've always believed in him and he's given the syndicate so much fun.
"The owners always back him hoping that the dream will come true.
"This is the biggest race we've ever won. I was up lambing at 2am so this makes it worthwhile.
"He's 13 so I don't think he'll be back next year, but never say never.
"Jamie was great on him, he's got a fantastic record on him, he's a great little jockey and rode a winner on the Flat at Doncaster just over a week ago."
There was a sad postscript to the race as the Ted Walsh-trained, Katie Walsh-ridden Battlefront collapsed and died after being pulled up at the 11th fence.
L'Unique (10-1) turned the form of the Adonis Hurdle on its head by giving Alan King a fourth victory in the Matalan Anniversary 4-Y-O Juvenile Hurdle.
The only filly in the race, she had finished behind Irish Saint and Vasco Du Ronceray at Kempton in February but the decision to miss Cheltenham and the Triumph Hurdle paid dividends.
King said: "I think not running at Cheltenham probably helped her and she seems to go on any ground.
"Beforehand I'd have been happy with being in the first four but that's a wonderful start.
"That's her for the season as we resisted entering for Punchestown. She'll have a good summer off and there are lot of a mares' hurdles to look at for next year."
Colin Tizzard's veteran Oiseau De Nuit (20-1) provided young jockey Brendan Powell with an Aintree winner to follow up his Cheltenham success in the matalan.co.uk Red Rum Handicap Chase.
Winner of the Grand Annual at Cheltenham back in 2011, Oiseau De Nuit has struggled being high in the weights ever since.
Powell said: "I can't believe how well this year has gone, it's been a dream come true to win at Cheltenham and now here."
Tizzard, whose horse has been placed in this race twice previously and was sixth last year, said: "That was a young man's stride he saw at the last.
"I was watching it with Terry (Warner, owner) and I thought we were beaten but then he came back on the bridle.
"To win this at 11 is some effort."
Powell later took the Silver Cross Handicap Hurdle on Kevin Bishop's 8-1 co-favourite Battle Group, who won the corresponding race two years ago when in the care of David Pipe.
A spring-heeled display of jumping secured the spoils for Captain Conan (6-5 favourite) as he pulled away up the straight to win the Betfred Manifesto Novices' Chase, his third Grade One win of the season and fourth in all.
Nicky Henderson's charge had faded into fifth in the Jewson at Cheltenham but on quicker ground he looked much more at home.
Lucinda Russell's Tap Night ran a career best to take second, three and a quarter lengths behind the impressive winner.
Henderson said: "This horse was always going for the two-mile race on Saturday, but I just thought this looked easier as Overturn and Alderwood were in the other race.
"Two and a half has helped us. He won it well and jumped great. He's finished for the season and it will be difficult next year but the owners are great mates and will have a lot of fun."