Big favourite Faugheen under Ruby Walsh suffered a surprise defeat as Sharjah, ridden by Paul Townend, won Sunday's Morgiana Hurdle at Punchestown.
With main rival Samcro withdrawn, Faugheen was sent off at odds of 2/5 but the crowd was silenced as 7/2 shot Sharjah forged to a clear victory.
With Jessica Harrington's Supasundae also withdrawn, there were just four runners for the Grade One feature.
Tombstone finished third ahead of Wicklow Brave who trailed throughout.
With the reduced field, former champion hurdler Faugheen appeared to face a straightforward task.
Walsh set out to make on Faugheen, who was last seen winning over three miles at Punchestown, and was dropping back to two this time.
Rachael Blackmore kept him honest on Tombstone, the only one of the four eventual runners not trained by Willie Mullins, but he dropped away before the turn into the straight.
Just when Faugheen looked set to go clear though, Sharjah, a Galway Hurdle winner but beaten behind Bedrock and Samcro at Down Royal, cruised past him to win by seven and a half lengths.
Townend said: "That was pretty straightforward for a Grade One.
"I travelled well the whole way, got the feeling Ruby was in a bit of trouble when I was still doing it well and I had fitness on my side.
"The ease of the win surprised me a bit, but he promised to win a big one a few times last season. I wouldn't write Faugheen off."