Admiral Brian was a most fortunate winner of Clonmel's Jim Strang & Sons Kilsheelan (Peugeot) Hurdle.
Coquin Mans was all the rage for the three-mile contest and after tracking the front-running Val De Ferbet, moved upsides four out.
He went to the front just after the next and was in command early in the straight when he stumbled on the level and came down.
That left Admiral Brian just in front of Taglietelle and although both were tired, Eamonn O'Connell's 25-1 outsider kept going under the trainer's son Eoin to score by two lengths.
O'Connell snr said: "We didn't expect it today but he won and we'll take it.
"That's his first time running over three miles - we've been running him over two miles and he handled the ground well there when a lot of them didn't.
"He is consistent and we might go over fences now or else go to Leopardstown over Christmas for the Pertemps Qualifier."
Coquin Mans' jockey Paul Townend said: "I went back and had a look on the track and couldn't see any massive hole or anything. It's hard ground to gallop on, but it was no worse there than it was the whole way round. It's just one of those things, I suppose.
"You're on the ground before you know what's actually happened. You've no chance to brace yourself. It could have been a lot worse, but it's still very disappointing. It was going to plan and then fell apart."
Trainer Willie Mullins said: " Coquin Mans was very unlucky and sustained a nice little injury on his knee so we won't see him at Christmas anyway. Paul said there was nothing wrong and just tripped up."