Unowhatimeanharry bounced back from his Cheltenham defeat by winning the Champion Stayers' Hurdle on day three of the Punchestown Festival.
The Harry Fry-trained nine-year-old just beat Cheltenham winner Nichols Canyon in a tight finish.
Unowhatimeanharry, ridden by Cork jockey Noel Fehily, had won eight races in a row before Cheltenham.
He won at 4-1, while runner-up Nichols Canyon was 7-4 favourite and the 9-1 shot Footpad came third.
"Cheltenham was not meant to be for us but to bounce back in the manner he has done and really tough it out all the way to win is fantastic," said winning trainer Fry.
Nichols Canyon, ridden by Ruby Walsh, looked to be in with a good shout of confirming the Cheltenham form in the finishing straight.
Noel Fehily had kicked on some way out on Unowhatimeanharry and stole a few lengths, but Walsh still looked confident on jumping the last a length down.
However, while he was edging closer with every stride, the post appeared just in time to give Fry one of the biggest wins of his career.
Victorious jockey Fehily said: "I just thought we went very slow. Plans A, B and C went out of the window because the last thing I wanted was to be in front two out.
"I had to go forward but luckily he's a tough little horse, he was very long at the last but he came up for me and he's got the heart of a lion."
BBC horse racing correspondent Cornelius Lysaght:
Another thrilling finish but Nichols Canyon's trainer Willie Mullins could have done with the first-place prize money for the champion trainer's title race.
As with Djakadam on day two, inches have cost him dear and, despite some success on the undercard, the gap to Gordon Elliott remains stubbornly wide.
Of course, he will have masses of runners during the last two days of Punchestown, so anything is possible, but you can't help feeling it is (mostly) just not happening for Mullins at the moment.