A last-minute try from Matt King and a conversion by Chris Hicks gave the Wolves victory in an extraordinary match at the KC Stadium.
This was arguably a game which neither team deserved to lose, but based on their errors, neither deserved to win.
Warrington did so, however, with seconds remaining, when a penalty conceded by the Hull captain Lee Radford put them on the attack, and the previously anonymous King went over from Michael Monaghan's pass.
That still left Hicks who had endured a mistake-ridden afternoon, to kick a difficult conversion, which he put over with a strange, curling effort with the outside of his right boot.
"Chris is a very positive player," said the Warrington coach, James Lowes, "what you want is, if you make a few mistakes, you forget about them until the end of the game."
This was indeed a game riddled with mistakes, first exploited by Shaun Berrigan, to exchange passes with Kirk Yeaman, to put Hull ahead.
Kevin Penny, back in the Warrington side, took an interception from Danny Washbrook to go 90 metres for the equaliser but Berrigan's second put Hull ahead at half-time.
They should have been in a stronger position still when Paul Rauhihi was sent to the sin-bin just before the break. "But our start to the second-half was woeful," said the Hull coach, Richard Agar.
That start saw Lee Briers' try bring 12-man Warrington level but Hull led again when Jodie Broughton capitalised on some slick handling to claim his first try for the club.
A turning point in the game came with a bizarre try when Briers waited for Danny Tickle to get to his feet and then stole the ball from him to set up Penny's second.
Hicks kicked Warrington ahead, but Hull still looked likely winners after they chose to run the ball rather than kick for a draw and Yeaman got in. But Hull failed to close the game down in the last minute, turned over possession yet again and paid the penalty.
Hull: Sing; Briscoe, Broughton, Yeaman, Raynor; Washbrook, Dykes; Dowes, Berrigan, Carvell, Manu, Tickle, Radford. Substitutes: Thackeray, Houghton, Wheeldon, Burnett.
Warrington: Hicks; Riley, Grix, King, Penny; Briers, Monaghan; Parker, Clarke, Rauhihi, L Anderson, Blythe, Harrison. Substitutes: Morley, Westwood, Cooper, Gleeson.
Referee: S Ganson (St Helens).Reuse content