Simply Ned lunged late to successfully defend his crown and cause another big upset in the Paddy's Rewards Club "Sugar Paddy" Chase.
The Nicky Richards-trained veteran had made five previous appearances at Leopardstown, finishing out of the first three just once.
The 11-year-old enjoyed his day in the sun when claiming this prize last season - passing the post narrowly behind the Willie Mullins-trained Min before the result was reversed in the stewards' room - and he was sent off at 16-1 for a repeat.
Mullins once again fielded the hot favourite in Footpad [evens], who was bidding to bounce back from a disappointing comeback run at Naas.
For much of the two-mile journey everything appeared to be going to plan for the market leader, who jumped accurately under Ruby Walsh and swept to the front on the run to the final fence.
He looked to have victory in the bag after setting off up the run-in, but Mark Walsh conjured a late run out of Simply Ned and got up to score by half a length.
Mullins' second string Great Field made much of the running, but appeared booked for a place at best when crashing out at the final obstacle.
The JP McManus-owned Auvergnat emerged a surprise winner of the Paddy Power Steeplechase.
Usually geared towards cross-country races by Enda Bolger, jockey Donie McInerney steered Auvergnat to the win ahead of the game Vieux Morvan and Fitzhenry with 5/1 favourite Any Second Now back in fifth.
Auvergnat returned at 28/1.
The day finished on a sad note for McManus however as veteran star Carlingford Lough died after collapsing on course.
He won five Grade 1s under trainer John Kiely.