Betfred Super League
Hull FC (4) 4
Warrington (12) 18
Tries: Williams, Dufty, Ashton Goals: Ratchford 3
Warrington beat fellow play-off hopefuls Hull FC to win for the first time in nine games and revive their push with four rounds left.
Adam Swift swiped a loose ball to put Hull ahead before two superb tries from Wires George Williams and Matt Dufty.
The Wire kept Hull out with stubborn defence before Matty Ashton went over from a fine, looping Williams pass.
Hull's loss is a huge dent to their play-off hopes, as four points now separate them from the top six.
Jake Trueman limped off five before the break with what head coach Tony Smith described in his post-match presser as a ruptured Achilles, a further blow to the Black and Whites.
Having had chances to end their miserable run last weekend in defeat by Leeds, Warrington arrived in East Yorkshire desperate to impress but soon found themselves behind.
After a sharp start full of intent from the Wire, the home side were handed a gift as a move to the right went to ground and Swift pounced to race away.
Yet a powerful forward pack, led by Paul Vaughan and Thomas Mikaele, with James Harrison from loose-forward, continually pummelled out a platform for their craftsmen to profit.
Williams pushed up to support a neat break from Josh Thewlis and Dufty before taking the final pass to dot down under the posts, and then put his creator through a gap and the Australian's raw pace and footwork did the rest.
Hull sweated in their bid to get back into the game, with packmen Chris Satae and Brad Fash doing big minutes, but could not breach a scrambling Wire defence.
In reply, the game-ending moment saw Williams slip a peach of a rainbow pass to the sideline for Ashton to dot down, after the home defence had jammed in.
Tony Smith's side are not mathematically out of the play-offs equation, but with other sides so tightly packed in above them, it will take a remarkable sequence for them to squeeze into the pack.
Hull FC head coach Tony Smith:
"I didn't think it was a great game. I thought both teams were pretty sloppy and Warrington were slightly better than us and deserved to win.
"They came up with a few plays which rewarded them with points, and we didn't. We just weren't able to execute well enough to get over the line.
"I thought we were sloppy in defence at times, but at times showed some real fight and pride on our try-line. But the number of times we slipped off tackles wasn't great. It was the same in attack. Balls not hitting the mark was happening too often.
"Whether we can make the six or not, rugby league is about pride and competing regardless. Everybody wants to fight for the badge and that's what we're instilling in this team."
Warrington interim coach Gary Chambers:
"The boys are certainly happy, they're up in the changing rooms and they deserved it. They worked really hard. It wasn't enlightening rugby, but we put in plenty of effort and we'll get better.
"It's a whirlwind. I came in three weeks ago and haven't slept much.
"It's a challenge for me and I'm learning, but to get a win today is great for the players and great for the fans as well."
Hull FC: Leeds (h), Castleford (a), Huddersfield (h), St Helens (a)
Warrington: Castleford (h), Salford (a), St Helens (h), Huddersfield (a)
Hull FC: Litten; Swift, Sutcliffe, Scott, McIntosh; Trueman, Clifford; Fash, Dwyer, Satae, Lane, Savelio, Cator
Interchanges: Brown, Gardiner, Lovodua, Shaul [Staveley]
Warrington: Dufty; Thewlis, Mata'utia, Ratchford, Ashton; Williams, Drinkwater; Mikaele, Walker, Vaughan, Currie, Nicholson, Harrison
Interchanges: Clark, Kasiano, Philbin, Crowther [Hayes]
Referee: Chris Kendall.