Minella Indo won the Cheltenham Gold Cup on Friday to make Henry de Bromhead the first trainer to win the Champion Hurdle, Champion Chase and the blue riband event at the same festival.
Jack Kennedy guided Minella Indo home ahead of another de Bromhead runner, A Plus Tard, ridden by Rachael Blackmore, with two-time defending champion Al Boum Photo third.
De Bromhead landed the Champion Hurdle on Tuesday with Honeysuckle as Blackmore became the first female jockey to win the race and on Wednesday Put The Kettle On won the Champion Chase.
"I think I am still in my hotel room on Monday night and nothing has started," he said after sealing the so-called "Holy Trinity".
"It is amazing... just brilliant. I am delighted. It is unbelievable to go and do it with him (Minella Indo), he is an incredible horse. It is amazing he just comes alive here."
Irish jockey Kennedy, 21, who missed last year's Cheltenham Festival with a broken leg, said he had dreamed of winning the race since he was a child.
"I'm so grateful to Henry for giving me the opportunity to ride him," he said. "I can't thank them enough and I'll owe them forever."
For Kennedy it was the supreme reward after many serious injuries in his short career.
"This is what I live for," he said. "I can't believe this is happening. I'm delighted."
The Irish 1-2-3 underlined their dominance of the festival. The best-placed English horse, 2018 champion Native River, finished a distant fourth.
The signs had not been good for the home challenge when both the fancied horses of trainer Nicky Henderson failed to make it out for the second circuit.
Champ, named in honour of legendary jockey AP McCoy, never settled from the moment he made a jumping error at the first fence.
Nico de Boinville pulled him up midway through the first circuit. Champ's stablemate and last year's runner-up Santini was also pulled up by Aidan Coleman.
Frodon and England's leading female jockey Bryony Frost could dream for a while of glory.
However, their dreams disappeared as both Minella Indo and A Plus Tard loomed on the final bend, with Al Boum Photo also threatening.
Al Boum Photo, the winner in 2019 and 2020, could not find the extra gear, leaving the two De Bromhead runners to battle it out for the win.
Blackmore had to accept second best but sportingly clasped hands with Kennedy.