Veteran half-back Brad Davis rolled back the years with a vintage display to help give Super League's bottom club Castleford renewed hope of avoiding the drop.
The 36-year-old Davis, Super League's oldest player now in his second spell with the Tigers, scored his side's first try and had a hand in the next five to guide the Yorkshiremen to a precious second successive home win.
Davis, who is taking a break from his stint as player-coach with French club Villeneuve to spearhead Castleford's relegation fight, earned a standing ovation from the home crowd after his brilliant man-of-the-match performance.
After posting their biggest win for 14 months, Castleford now trail London Broncos by just a point and are four behind Widnes, whose search for a new coach will receive added impetus after this ghastly show.
The Tigers had the game sewn up by half-time after dominating the first 40 minutes and outscoring the Vikings by five tries to nil.
They gained the upper hand in the forward battle, with Andy Lynch and Michael Smith leading the way, and that gave Davis the platform to display his attacking skills.
The former Wakefield skipper scored the game's first try after only two minutes, slicing through a defence pulled out of position by a rampaging run from skipper Ryan Hudson.
Widnes pulled two points back with a Stephen Myler penalty to make it 6-2 but they badly missed chief playmaker Jules O'Neill, sidelined with a hamstring injury, and rarely threatened the home line.
The Tigers, conversely, were full of life and they doubled their lead on 21 minutes when Smith took Davis' cut-out pass and drew the defence to send winger Paul Mellor over.
Mellor then palmed back a high kick from Jon Hepworth into the hands of Davis for Smith to finish off and Francis Maloney, filling the club's problem scrum-half role on his return from injury, squeezed over at the corner just before the break after taking another pass from the mercurial Davis.
Widnes briefly threatened a comeback when hooker Shane Millard forced his way over from dummy half for a converted try but Davis produced an array of tactical kicks to keep his side on top.
And it was from his pass that full-back Damien Gibson carved out an opening for Mellor to grab his second try on 55 minutes to put the game safe.
Hooker Wayne Godwin then jinked his way over for a try and kicked his fifth goal from eight attempts.
Widnes' ignominy was compounded by the late sin-binning of full-back Paul Atcheson for delaying tactics and Castleford took advantage to score an eighth try through centre Darren Rogers.
Wakefield Wildcats completed the double over Tetley's Super League relegation rivals Castleford on Sunday to hit the top six for the first time this season.
Five tries in the second half - and two scored in the opening four minutes of that half when Wakefield were down to 12 men - turned the game on its head.
Cas rallied at the end and scored consolation tries as Wakefield tired through Steve Crouch, on his debut, and former Wakefield player Brad Davis.
Scrum-half Ben Jeffries turned the tide with two tries in the first 11 minutes of the second half and he made another for skipper Gareth Ellis on the hour mark.
Sid Domic and Jason Demetriou bagged the other tries while Jamie Rooney tagged on goal points plus a 57th-minute field goal.
Just two points separated two well-matched sides at half-time with Wakefield holding a slight advantage at 10-8.
The first half had see-sawed with Rooney nosing the hosts ahead with a penalty in the ninth minute.
But Castleford took control and went 6-2 up with a Jon Hepworth try, converted by hooker Wayne Godwin midway through the half.
Rooney reduced the arrears with a second penalty, that also cut the Tigers to 12 men for 10 minutes, before centre Demetriou scrambled over for Wakefield's opening try just after the half hour, converted by Rooney.
Cas had a chance to at least level in the 39th minute but former Wakefield man Francis Maloney bounced the ball over the line.
But seconds from the break Ellis was sin-binned for holding down and Hepworth took the gap with the resulting penalty conversion to throw the game wide open again.
But in the second half the home side took control and were indebted to tries those five tries which gave the game a very one-sided look.
Catastrophic defending handed winger Waine Pryce two early tries and bottom club Castleford a Tetley's Super League survival lifeline at the Galpharm Stadium.
England A international Pryce, who is the cousin of Bradford Bulls star Leon, put the Tigers on course for only their fourth win of a troubled season inside 10 minutes.
Pryce bagged his opening try after only 90 seconds by simply carrying the ball over the line from Nathan Sykes' reverse pass following the prop's unchecked run through the entire Huddersfield back line.
Eight minutes later Pryce pounced on Huddersfield loose forward Stanley Gene's misplaced pass on the right flank to dart away into the corner.
And while Castleford hooker Wayne Godwin missed both conversions, he made amends later in the first-half by kicking three penalties to put the visitors into a comfortable 14-0 lead.
It was nothing less than the Tigers, fired up by second bottom Widnes' defeat yesterday, deserved for a tremendous performance.
Castleford moved the ball around with a verve and style that not even the top clubs in Super League have managed too often this season.
And on this kind of scintillating form it is hard to understand how Castleford - who fielded a strong-looking line-up featuring Brad Davis, Andy Lynch and Damian Gibson - have ended up in relegation danger.
Huddersfield had Hefin O'Hare's try ruled out before the interval for a forward pass in the build-up play, but they were back in the contest when substitute Paul White blazed through under the posts just after the restart.
Brandon Costin converted, and minutes later the Aussie playmaker put in James Evans for a touchdown to give the Giants some hope.
But the home side were sent crashing to their fifth straight defeat and their ninth in 11 games following an impressive scoring burst by Castleford.
Second-half tries from Ryan Hudson and substitute Mark Tookey plus a conversion and two penalties from Godwin and a Francis Maloney drop goal sealed victory.
Castleford have now done the double over their West Yorkshire neighbours following a 24-20 victory over the Giants at the Jungle in July, and the latest victory gives them a fighting chance of beating the drop.
High-flying Hull were brought down to earth as basement club Castleford continued their recent revival.
The Tigers were full value for their surprise win that kept the pressure on the other relegation candidates.
Hull were already 18-8 down when prop Paul King was sent off in the 63rd minute for a high tackle.
The visitors made the first threat when Paul Cooke sent Kirk Yeaman on a promising run but the Tigers opened the scoring in the fourth minute.
Veteran Brad Davis' high kick caught out Hull's defence and Darren Rogers pounced for the opening try.
The same ploy then nearly worked again when Tom Saxton went close to scoring from a Davis kick to the opposite corner.
Wayne Godwin edged the Tigers further ahead with a 15th-minute penalty goal before Hull had a let off when Davis re-gathered his own clever kick but his pass failed to find the supporting Waine Pryce.
Castleford's domination was rewarded when Godwin landed his second penalty to stretch their advantage to eight points.
Hull opened their account when Jason Smith made the opening for Cooke to score a 28th-minute try but the stand-off was unable to add the conversion.
Castleford's Lee Harland went over seven minutes later but the Tigers had to settle for two points from a penalty goal from Jon Hepworth because referee Richard Silverwood had already pulled up Hull for offside.
Castleford went close again early in the second half when Ryan Hudson fed Saxton who lost the ball just short of the line.
Hull's Nick Scruton then had a try ruled out for failing to ground the ball correctly.
The visitors were then reduced to 12 men when Richard Horne was sin-binned for obstruction.
Tigers soon capitalised when Hudson and Harland combined to set up a try for Damian Gibson and Godwin added the extras.
Hull struck back when Yeaman crossed from Cooke's pass to put them back in the hunt but then King then got his marching orders for a high tackle on Craig Greenhill and that signalled the end of their hopes.
Godwin kicked another penalty before Davis clinched victory with a dropped goal.
Davis was then sin-binned for interference before Hull completed the scoring with a late try from Richie Barnett jr, which Cooke improved.
Leeds Rhinos took a major step
towards their second Grand Final with a runaway victory over bottom club
Castleford to clinch top spot in Tetley's Super League with three games left of
the regular season.
The Rhinos picked up from where they left on in the 40-12 hammering of reigning
champions Bradford five days earlier with a 12-try rout of the relegation
favourites.
Tony Smith's men easily maintained their unbeaten record at Headingley to secure
the League Leaders' Shield for the first time for 32 years and, on this form,
will surely add the Super League trophy at Old Trafford on October 16.
The result leaves Castleford deep in relegation trouble after their points
difference, which could become crucial in the final reckoning, took a heavy
battering.
Architects of an impressive show were Great Britain centres Keith Senior, who
scored one try and supplied the passes for two by scrum-half Rob Burrow, and
Chev Walker, who scored two tries in each half.
Leeds made light of the absence of record try-scorer Danny McGuire as they swept
aside the Super League strugglers with contemptuous ease.
Second rower Ali Lauititi combined with the equally powerful Senior to set up
Burrow for his first try on nine minutes and they repeated the move three
minutes later.
Then Senior took Andrew Dunemann's inside pass to romp 30 metres for a glorious
try of his own and Kevin Sinfield's third goal made it 18-0 after only 21
minutes.
Castleford, without five senior players through injury, gave themselves brief
hope on 26 minutes when Australian Steve Crouch finished off a sparkling
handling move in which fellow second rower Lee Harland figured prominently.
Former Leeds half-back Jon Hepworth kicked the conversion to make it 18-6 but
Leeds produced some breathtaking rugby to run in three more tries before the
break.
Walker took Sinfield's pass to crash over wide out for his first try and
substitute Willie Poching squeezed a pass out of a two-man tackle for the
unmarked Marcus Bai to register his 23rd try of the season.
And another bumper Headingley crowd rose just before half-time to acclaim a
candidate for try of the season as Mark Calderwood broke from his own half
directly from the re-start and Jamie-Jones Buchanan continued the move for
Walker to finish off.
Sinfield's fifth goal from six attempts made it 34-6 at the break and it took
Leeds only two minutes to increase their lead, with the hugely impressive
Poching demonstrating his exceptional strength to reach out of a two-man tackle
and register his side's seventh try.
Castleford, who played with plenty of spirit, grabbed a consolation try on 48
minutes when 36-year-old Brad Davis raced onto a kick from skipper Ryan Hudson
and Hepworth kicked his second goal.
But the Rhinos were in simply rampant form and when Dunemann took Matt Diskin's
pass to cross for another try on 55 minutes it was the sixth game in a row in
which Leeds had topped 40 points.
They reached the half-century when towering prop Wayne McDonald crashed through
some flimsy tackling and Walker completed his hat-trick after gathering
Sinfield's clever lofted kick.
Leeds finished the game with 12 men following the sin-binning of Dunemann for
fighting but they still managed to add to their try tally.
Poching took a chip kick from Hudson and galloped 30 metres for his second try
and Walker added his fourth in injury time to complete the rout.
Leeds coach Tony Smith watched
his team secure the League Leaders' Shield after a 64-12 rout of Super League's
bottom club Castleford but warned the hard work is not over.
The Rhinos clinched top spot - and with it an easier route to the Grand Final at
Old Trafford on October 16 - with three games to spare after registering their
biggest-ever win over the Tigers.
"We are aware of what we've achieved so far but we've spoken about finishing
the last three games strong so that we go into the finals in good form," said
Smith.
"We're happy but we're not satisfied. We've got to get better. It's our desire
and ambition to get better each week. That's what is driving these boys
individually and as a team.
"They're enjoying it and they're ready to step up a gear or two."
Leeds ran in 12 tries, four of them from centre Chev Walker, and Smith admitted
that gives him a selection dilemma, with Chris McKenna and record-breaking
stand-off Danny McGuire fit to return at Wigan next week.
"I thought they played tremendous rugby league," he said.
"Kevin Sinfield was absolutely outstanding. He was involved in everything."
Castleford coach Gary Mercer, who rested three of his senior players
ahead of next week's crucial home game against Salford, admitted the scale of
defeat was particularly disappointing.
"That hurt me quite a lot," he said.
"We spoke at half-time about getting pride in our line.
"I thought the spirit was willing but we were beaten by a red-hot side. We
couldn't cope with their class and out-and-out pace.
"I was very disappointed with the referee's performance. I thought he was a bit
unfair in his decisions. I haven't moaned about referees all year but I have to
moan tonight.
"We have to regroup because we have a big test next Sunday against Salford."