JP McManus' record purchase was beaten by stablemate Constitution Hill in the opening race of the 2022 Cheltenham Festival.
Purchased for £570,000 by McManus in November 2020, Jonbon was beaten by 22 lengths as 9/4 favourite Constitution Hill powered up the famous Cheltenham hill.
The turning point of the Grade One was at the third-last flight, when the pace-setting Mullins-trained Dysart Dynamo crashed out, leaving the Henderson pair alone up front.
There was little between the duo going to two out – but Constitution Hill (9-4 joint-favourite) was going the better and soon took the lead.
The five-year-old, owned by Michael Buckley, quickly put daylight between himself and Jonbon to score by 22 lengths.
No other horse got into the race, with Kilcruit staying on to take minor honours another two and a half lengths away, as Henderson won the Supreme for a fifth time.
De Boinville said: “I knew it was going to be fast and furious and in fairness he did it like a piece of work. I was so happy going to the last. He could be anything, I’m sure he’d jump a fence as well. He’s got so much scope.
“I didn’t really have a choice (to go for home when he did), he was travelling so well. They’ve gone a really hard gallop and he’s just picked the bridle up. I’m delighted for his owner Michael Buckley, he’ll be ecstatic.
“What a way to start the week, what a legend.”
Henderson said: “That was awesome. I know what the second horse is and I would have been very surprised if anything could have done that to Jonbon, so he must be an extraordinary animal.
“The hype horse earlier on in the year was Jonbon, then this fella woke up from his slumbers at home and we suddenly realised that actually he was very good.
“He’s been very good but the big question was how much he actually knew, he’s run in two hurdle races with four runners in each. To suddenly go out there and go at that gallop, that’s the extraordinary thing.
“He can travel so easily at that pace and then pick it up, to find gears at the end of a headlong gallop like that was extraordinary.”
He went on: “I just feel sorry for Jonbon! The three of them, with Dysart Dynamo too, had pulled a long way clear when he fell and no one wants to see that.
“This is obviously a very good horse because we know Jonbon is a very good horse so for him (Constitution Hill) to do that to him is remarkable.
“He is extraordinary. Actually today was the first time he woke up in the stables before the race. They felt the atmosphere pre-race.
“I can’t believe he’s a genuine two-miler. He’d stay two and a half standing on his head, but he does have an enormous turn of foot.
“He’s always just racing two gears below everyone else because it’s all so easy and then you press a button and it works.
“In some ways he’s the perfect horse, but in others he’s hard to work as everything is so easy for him. In the last few weeks I’ve had to get horses to go with him, not Jonbon. It’s hard when a horse is that good, but good fun.
“That feels like a relief. That race was everything and now we can look forward to Shishkin.”
On plans for his winner, he added: “Someone tried to tell me to run him in the Champion Hurdle this year and I’ll get it in the neck for not doing it after a performance like that! We’ll see what the future holds.
“I think Aintree comes quick, but he could go to Punchestown.”
Gold Cup-winning jockey Barry Geraghty bought Constitution Hill as a store horse before selling him to Henderson, and admitted the feeling was completely different to anything he had experienced at Cheltenham before.
“You dream as a spectator to be involved, and then you dream of a performance like that, but at the same time you are afraid to dream,” he said.
“This is the moment that flashes into your mind, but you try not to let it because you don’t want to be disappointed.
“This horse has everything, he’s gorgeous in every sense, he just has so much class.
“He had all the right horses behind him, Jonbon ran his race, Kilcruit was there – we thought this lad could be exceptional and it looks like he is.”
Patrick Mullins, rider of Kilcruit, said: “We’ve gone a ferocious gallop and my lad was never able to lay up, which I thought he would.
“His jumping was a little bit scrappy. The ground is good and he probably wants a step up in trip.
“It was an exceptional winner. To go that strong a gallop and quicken off it, he’s an exceptional horse.”
Mullins senior said: “The winner was very impressive.
“I think Kilcruit and Bring On The Night both need an extra half-mile, on that sort of ground anyhow.
“Dysart Dynamo fell too far out (to know what would have happened), but it looked a tired fall, so maybe he had done enough at that stage.”
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