Percy, far side, leads Caro Des Flos home© Photo Healy Racing
Percy stayed on best up the hill in Downpatrick to collar odds-on-favourite Caro Des Flos in the opening maiden hurdle.
Caro Des Flos (2/5f) attempted to make all but Percy adopted a stalking brief and was unleashed after the last by Davy Russell to hit the front in the final 150 yards.
The 7/2 shot won by a length from Caro Des Flos with Percy's stablemate Sometimes A Fox seven and a half lengths back in third at 8/1.
Trainer Gordon Elliott said: "He was entitled to win it on his ratings on the flat. He'll even come on from a bit better ground.
"He definitely wants better ground so he might be a horse we'll keep for Punchestown for a winners' of one hurdle. He'll come on for that run."