Chris Dagnall scored twice as Scunthorpe put the departure of manager Nigel Adkins behind them with a sensational victory over Sheffield United.
The Iron - who lost Adkins to League One Southampton on Sunday - were on the back foot for long periods at Bramall Lane but eventually ran out convincing winners.
Dagnall opened the scoring in the first half with a powerful low shot, although the striker did appear to have controlled the ball with his arm before firing past Steve Simonsen.
David Mirfin headed a second for Scunthorpe after the interval before further goals from Dagnall and Martyn Woolford rubbed salt into the Blades' wounds.
The margin of defeat was harsh on the hosts, who struck the woodwork twice in the first half, saw two goalbound headers cleared off the line and also had a goal disallowed after the break.
But that will matter little to Scunthorpe caretaker boss Ian Baraclough, who can only have enhanced his chances of claiming the club's managerial reins on a permanent basis.
It was Gary Speed's men who started the quicker and they could have taken an early lead after good work from Stephen Jordan, but Jamie Ward's low shot thudded into the base of the post as Scunthorpe survived.
United rattled the woodwork again soon after as Ched Evans' low shot hit the post and deflected to safety.
And the hosts were hit with a sucker-punch as the Iron took the lead just after the half-hour when Dagnall opened his account for the evening by firing home a low effort from Cliff Byrne's cross.
Richard Cresswell squandered a good chance for United moments before Kyle Bartley's header was superbly cleared off the line as the home side searched for a leveller.
And they thought they had found it when Johannes Ertl volley home but referee Neil Swarbrick spotted an infringement in the Scunthorpe area.
But they soon found themselves further behind when Mirfin's superb diving header from Josh Wright's corner left Simonsen with no chance after 63 minutes.
The game was put to bed 10 minutes later when Dagnall capitalised on Nyron Nosworthy's untimely slip to advance on goal and round Simonsen.
Jonathan Forte could have scored against his former club but Simonsen produced a fingertip save, but the Iron were not to be denied a fourth in the dying stages as Simonsen's poor clearance found Woolford, who fired home into an empty net from 40 yards out as Scunthorpe ran riot.
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