Bapaume claimed the scalp of Landofhopeandglory in the Knight Frank Juvenile Hurdle at Leopardstown.
Landofhopeandglory headed the Triumph Hurdle market after winning his first three over timber, most recently defeating Bapaume in a Fairyhouse Grade Three.
Bapaume was having his first start for Willie Mullins that day, though, and has obviously come on for the run.
He and Landofhopeandglory jumped up either side of leader Zig Zag at the second-last and settled down to fight it out, but Bapaume found more reserves of stamina and scored by a length and three-quarters, with Mega Fortune only narrowly failing to catch Landofhopeandglory for second.
Boylesports cut Bapaume to 8-1 from 12-1 for the Triumph Hurdle and eased Landofhopeandglory to 10-1 from 6-1.
Joey Sasa stayed on strongly to claim top honours in the Thorntons Recycling Maiden Hurdle.
Barra took the lead off favourite Castello Sforza at the top of the straight, but Sean Flanagan had him in his sights on the Noel Meade-trained 3-1 chance.
Joey Sasa took it up at the final flight and saw out his race well to triumph by two and a quarter lengths.
Meade said: "He was beaten by a good horse in Navan (Cilaos Emery), and I really thought he would win today.
"Sean said the ground was a help, he felt it was yielding with no soft in it."
Bunk Off Early made a victorious start to his jumping career in the Horse & Jockey Hotel Maiden Hurdle at Leopardstown.
Willie Mullins' grey disputed the lead with Imperial Way until a slick leap two out carried him a couple of lengths clear.
As Imperial Way faded, his stablemate Outspoken emerged as the main threat but Ruby Walsh had not pressed any buttons on 7-4 favourite Bunk Off Early, who quickened again and passed the post with five and a half lengths in hand.
The winner was given a 16-1 quote for the Supreme Novices' Hurdle at Cheltenham in March by Paddy Power.
Walsh said of the Supreme Horse Racing Club-owned winner: "He was a bit keen. He jumped well and quickened smartly to win. It was a good performance."