Nick Powell scored his first goal since joining the club in the summer to cancel out Mark Duffy's first-half strike past former Iron loanee Sam Johnstone, who received a warm welcome on his return to the club.
Federico Macheda had the ball in the net in only the third minute but the lone striker was flagged offside and jeered for much of the first half for smashing a volley over the bar when the whistle had already sounded. United pressed without really penetrating the home defence as Sam Slocombe fielded a Jesse Lingard shot and found a Powell drive too hot to handle after the ex-Crewe man unloaded a fierce drive.
Although Johnstone had made a couple of punches, the opening goal was somewhat against the run of play but superbly worked. Mike Grella won possession and fed Bobby Grant, who turned Michael Keane before teeing up Duffy for an emphatic finish that lifted the home crowd.
The Reds tried to respond but Davide Petrucci fired tamely at Slocombe after a neat spin and Bebe pulled an effort wide after Petrucci won a crunching tackle in midfield. Robbie Gibbons went to ground easily under minimal contact from Marnick Vermijl so the referee Darren Drysdale rightly refused half-hearted penalty claims and Bebe's hopeful poke straight at Slocombe ended the first period in terms of entertainment.
In a dramatic start to the second half, Petrucci and Macheda set up Powell for a stinging shot that brought the very best out of Slocombe, who dived to his right to pull off a marvellous save. Scunthorpe had a much clearer shout for a penalty turned down when Grella was sent tumbling by Keane's over-zealous challenge with referee