Scunthorpe let a two-goal lead slip to be defeated 3-2 at Stoke City.
Martin Paterson put the visitors ahead early on, and then Jack Hobbs' header added to the score as United went in two goals ahead at half-time.
However, the hosts hit back in the second half and struck through Liam Lawrence, Richard Cresswell, and then Lawrence again to seal a big win for them, and a bad loss for the North Lincolnshire side - who looked so comfortable at half-time.
The Iron made three alterations from the team that lost at home to Bristol City on Tuesday.
Andy Butler replaced the injured Cliff Byrne in the starting eleven, while Paul Hayes and Kevan Hurst dropped out at the expense of Matt Sparrow and Ian Morris on the flanks.
Starting in goal was Joe Murphy, with Hobbs (at right-back in place of Byrne), Andy Crosby, Butler and Marcus Williams completing the back four.
The midfield comprised of Sparrow, Jim Goodwin, Jack Cork and Morris, while Geoff Horsfield and former Stoke academy product Paterson led the line.
The substitutes' bench consisted of goalkeeper Josh Lillis, plus Hayes, Jonathan Forte, Ben May and Izzy Iriekpen - who was back from a long-term injury lay-off.
Victory for City would have seen them reach the top of the table, while the bottom-placed Iron could climb out of the relegation zone with a win at a packed Britannia Stadium.
The Iron were wearing their white away strip, and backed by a sizable away following - who had braved the cold to make the journey to the Potteries on a Friday evening.
The hosts kicked the game off and won a couple of corners in the opening stages, looking to make their superior height advantage count. However, Scunthorpe easily soaked up the pressure and looked to break through the pace of Paterson.
And it was the former Potters hitman who had the game's first real chance on seven minutes - and he took it to give Scunthorpe the lead.
Good link-up play from Horsfield brought Sparrow into play, and he clipped in a cross from the right wing which a free Paterson volleyed past Steve Simonsen.
The ex-Everton 'stopper got a touch to it, but it only delayed the inevitable as the ball crept in - and the Iron's leading goalscorer celebrated his 13th strike of the season in front of the travelling Scunthorpe contingent behind the goal.
The league's bottom team weren't expected to do this, and they kept up the pressure as the Britannia Stadium was shell-shocked.
City had let all the supporters who had backed the club at home to Southampton on Tuesday night in for free, and a carnival atmosphere was in full flow before kick-off - expecting to see their team roar to the top of the table.
Thus far, it was a vintage 'in your face' United display as they refused to let the Potters settle into their stride.
Already, 15 minutes in, the Stoke support were getting on their team's back - frustrated with attacking moves breaking down.
And, on 22 minutes, it was going to get even better for the Iron - who were enjoying the better of the game.
Morris' corner from the left was thumped home by the head of Hobbs from 12 yards, leaving Simonsen helpless, as the visitors raced into an unlikely 2-0 lead.
The home support couldn't believe what they were seeing and the arena became silent, but for the superb Scunthorpe contingent who were singing the theme tune to the Great Escape. As it stood, their side were out of the bottom three - and they were loving every moment of it.
The hosts were presented with their best opportunity of the game so far on 30 minutes when Leon Cort got on the end of a corner by Lawrence from the right. It was the first time that Iron goalkeeper Murphy had really been tested and the maiden occasion this evening when their supporters had being excited.
Even though United were successfully stifling the Potters, they worked one more decent chance before the half-time interval - with Fuller manoeuvring his way into space on the right-hand side of the penalty area on 40 minutes to scramble a low drive into Murphy's left side-netting.
A section of the home support thought it was a goal but their joy was short-lived as the other side of the ground remained still. As a result, Scunthorpe went in two goals up at half-time - but had to be wary of a Stoke onslaught at the beginning of the second period.
Horsfield was replaced shortly after the interval, with Hayes coming on for the on-loan hotshot.
The home team were handed a huge boost on 53 minutes when they pulled a goal back. Lawrence, the match-winner in their 3-2 success at Glanford Park earlier in the season, capitalised on a goalmouth scramble after Rory Delap's long throw to thump the ball low and hard past Murphy from ten yards.
The goal galvanised the City support, who roared every attacking touch of the ball from their side. Scunthorpe knew they were in for a game in the second half as the Britannia Stadium started rocking.
They thought their team had levelled on 59 minutes when Fuller headed home from a Cort flick-on, but the strike was disallowed for offside.
However, it didn't take them long to grab an equaliser which was seemingly more and more likely, as substitute Cresswell slotted the ball past Murphy from close range after Fuller's charge down the right.
The home team were well and truly back in it now and seemed most likely to get a win. It is harsh, but it is the way things go when a team is sitting towards the bottom of the table.
Using the never-say-die attitude instilled into them by their manager, United kept attacking - and Morris tested Steve Simonsen with a looping header from the left-hand side of the penalty area after Stoke failed to clear their line, and then, on their next attack, City added their third through Lawrence, always a thorn in Scunthorpe's side.
Fuller went on a storming run to leave three defenders floundering before setting up a tap-in for Lawrence.On 70 minutes.
As the game wore on, speculative passes which were reaching players in the first half were no longer sticking, and the hosts had the 'rub of the green'.
Scunthorpe made their second alteration on 84 minutes when Forte replaced Morris, in an attempt to add fresh legs to the Iron midfield.
Goodwin fired just over the crossbar from 25 yards with a thunderbolt of a shot after a pass from the left by Paterson.
Then, shortly after, Murphy's long punt upfield from a free-kick reached Forte, who turned and shot well wide. It was an effort which epitomised the Iron's luck in second half
There was one last throw of the dice by Scunthorpe boss Adkins, with May replacing Sparrow in stoppage time, but they couldn't create another opportunity and Stoke took he points.
The Iron are next in action on Tuesday night when they visit Wolverhampton Wanderers.
Apologies for the lateness of the Stoke City post-match coverage but, due to technical problems beyond our control at the Britannia Stadium, we could not bring it to you immediately after the game.

















