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 at 4/1 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, now on to four winners for the week 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."
Henderson added: "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."
Henry de Bromhead felt the race had not really worked out in Sizing Europe's favour, particularly as they had to bypass the last obstacle.
He said: "We were beaten which is about all I can say on the matter.
"It was an incident-packed race. We lost Wishfull Thinking at the second and we could have done with a lead for longer.
"Andrew tried to hug the rails all the way just like last year and he didn't know he was going to have to miss the last, we haven't really discussed it but he just said 'the last cost me the race'.
"We could have done with jumping another fence as he always likes something to aim at.
"These things happen and I wouldn't like to say much more."
To add insult to injury for Andrew Lynch, he was also penalised by the stewards for his use of the whip on the runner-up.
He was banned for six days (28-31 March and 1-2 April) for using his whip in an incorrect place.
Despite Big Zeb finishing some way behind the front pair, trainer Colm Murphy was satisfied with his effort. "He's got a phenomenal record in the race and he's run a blinder," he said.
"He's galloped right to the line but they went plenty quick enough for him. He will probably go to Punchestown."
Big Zeb's jockey Robbie Power admitted his mount had struggled to make his mark.
He said: "No excuses, he wasn't able to lay up them the way he used to. Old age has caught up with him but he ran his heart out."
It was later confirmed that Johnson had been stood down for the rest of the day but he is thought to have suffered only soft-tissue damage.
A French photographer at the second fence was hurt in the incident but was not thought to be seriously injured.