They spent just 25 seconds of the match on level pegging, with Nicky Wroe getting the first of his three strikes in the opening half-minute.
He finished off a good knock down in the box by Jake King and struck again after 28 minutes, sweeping home first time a low cross from the right. King was again the provider.
Seven minutes later he completed his hat-trick from a short free-kick routine, cracking home a shot from the edge of the box that took a deflection to beat keeper Sam Slocombe.
The Iron had been down to 10 men when they conceded, with captain Paul Reid off receiving treatment for a cut above an eye. David Mirfin came off the bench to replace him, with his side trailing by three goals.
Shell-shocked Scunthorpe, with only one home win all season, hit back after 41 minutes when striker Leon Clarke, on loan from Charlton, netted his seventh goal in 10 games, forcing the ball home at the second attempt after his first header had been half-blocked by keeper Steve Simonsen.
They then got themselves right back in the picture after 72 minutes when Karl Hawley crashed a spectacular 25 yard shot into the back of the net off the inside of a post.
It was the first time in 20 games that Scunthorpe had scored more than once in a match.
And only a great save by keeper Steve Simonsen then denied Clarke a late equaliser for Scunthorpe, who have taken only two points from their last six games.