Scott Dureau finished his afternoon in hospital having X-rays on a neck injury, but not before he had inflicted Warrington's first defeat since the first week of the season.
The Australian scrum-half scored a brilliant try 10 minutes from the end and kicked the goal to complete the Dragons' fourth fightback of a pulsating match.
Having got their flared nostrils in front for the first time, they clung on even without Dureau, who was carried off on a stretcher after a tackle from Garreth Carvell. His club were hopeful last night that he would be given the all-clear after treatment for whip-lash injuries, thus not taking too much of the gloss off a memorable victory.
"Warrington are as good as any NRL team," the Catalans coach, Trent Robinson, said. "But you've got to have belief. You can't write yourself off."
Considering the odds stacked against them, the Dragons did remarkably well to be level at half-time. Already without a number of their more influential players, they lost full-back Clint Greenshields with an elbow injury in an early tackle. They also quickly fell behind, Warrington moving the ball wide with their characteristic pace, Brett Hodgson and Chris Bridge setting up Joel Monaghan for his first try.
The Dragons were then denied their first real scoring opportunity, Dureau intercepting and threatening to go the length of the field, only to be brought back for a knock-on.
The French side had not come to feel sorry for themselves, however. By the 13th minute, they were level, after David Ferriol and Sebastien Raguin opened up the left flank for Cyril Stacul.
The Wolves went ahead again when David Solomona pounced on a loose ball and Hodgson again teed-up Monaghan, but Catalans remained full of fight. Five minutes before half-time, an attempted pass from Solomona to Rhys Evans went to ground and Frederic Vaccari scooped it up to go 70 yards for a second equaliser. Warrington led yet again early in the second half, Evans putting Chris Riley over.
The hugely impressive Ferriol responded with the sort of try prop forwards dream about, taking a short pass from the livewire Eloi Pelissier, beating the first tackle and finding the try-line.
The fourth time the Wolves got in front, it was thanks to a classic scrum-half's try from Richie Myler, selling a dummy and straightening up to go through the gap he had created. Surely, this time, it would be enough, but the French side would not lie down. Warrington have won plenty of matches on Lee Briers' kicks. This was one they lost on one. Myler knocked the ball down, Dureau pounced and the most surprising scoreline of the season so far was up in lights.
"You can lose to anyone in this competition if you're not at your best," said the Super League leaders' coach, Tony Smith. "And we were very far from our best."
Warrington Hodgson; J Monaghan, Bridge, Evans, Riley; Briers, Myler; Morley, M Monaghan, Carvell, Grix, Blythe, Clarke. Replacements Wood, Higham, Solomona, Cooper.
Catalan Dragons Greenshields; Vaccari, Baile, Millard, Stacul; Farrar, Dureau; Ferriol, Henderson, Casty, Menzies, Raguin, Mounis. Replacements Simon, Martins, Baitieri, Pelissier.
Referee P Bentham (Warrington).