Finian's Rainbow completed a magical afternoon for trainer Nicky Henderson and jockey Barry Geraghty as he landed the sportingbet.com Queen Mother Champion Chase at Cheltenham.
The duo had earlier claimed two Grade One victories, and Finian's Rainbow topped off the day in style as he overturned defending champion Sizing Europe after a thrilling finish.
The last fence was dolled off after an nasty fall on the first circuit and Finian's Rainbow passed the post a length and a quarter to the good after a long run up the hill.
The two-mile championship was an incident-packed race with Kauto Stone, half-brother to the great Kauto Star, crashing out at the very first obstacle.
Wishfull Thinking rocketed to the front under Richard Johnson and was pulling strongly before clattering the fence in front of the stands and suffering a nasty fall which saw him tumble through the rails and apparently into a crowd of bystanders.
That left 4-5 favourite Sizing Europe in front and Andrew Lynch was obliged to make the running with Geraghty hunting him round while the other runners just fell away.
Former champion Big Zeb just could not go with them and it had turned into a clear match race some way from home.
A lacklustre leap from Sizing Europe gave Finian's Rainbow a chance to move upsides and the pair were neck and neck at the top of the hill.
With the last fence out of action due to Wishfull Thinking's fall, Geraghty held the best position on the outside and he utilised that to the full as the pair had to steer past the last.
With his momentum checked slightly again, Sizing Europe was headed and could not find the extra gear required to peg back the 4-1 winner.
Big Zeb plugged on for a 15-length third.
Johnson was stretched into the racecourse ambulance as a precaution but was conscious and talking to officials.
Geraghty said: "It's a brilliant day - you dream of days like this.
"I'm genuinely so delighted for Michael Buckley (owner), he has a good team of horses and he's been unfortunate with Spirit Son getting injured.
"He's had a good few disappointments this season, but he's had patience with this fellow and I really am delighted for him.
"I thought he had it to do to be honest, but he has turned the corner since Ascot. His work has been much better.
"We were hoping he was closing the gap but you couldn't say for certain that he was there. We know now he was."
Buckley said: "I'm speechless, to be truthful. I'm feeling remarkably emotional.
"It's true to say I wouldn't have any jumpers if it wasn't for Nicky. We've been together as owner and trainer and friends since the early 1980s.
"I can't imagine doing it with anyone else and this is just another notch in his long career.
"He (Henderson) has scooted past the all-time record (as winning-most trainer at the Festival) and I'm proud and pleased to be part of the day."
Henderson said: "It was a great race and it was a pity they didn't jump the last fence. It was a tremendous race between two very good two-mile chasers.
"I'm thrilled for Michael because he's put a lot into this game, he adores it and it's a special day."