Scunthorpe netted their best result of the season and only their third home win in a 6-2 hammering of Huddersfield.
The Terriers are proving poor travellers, with only one win so far, and they can have no complaints over this result after being reduced to 10 men after 53 minutes.
Lee Fowler was dismissed for what his manager Peter Jackson described as a "stupid tackle" and that cost them dearly after fighting their way back into the game with an Andy Booth goal just after the break after finding themselves 2-0 down at the interval.
Scunthorpe made a slow start but they took the lead through a Peter Beagrie 17th minute free kick.
Steve Yates then cleared off the line from Matt Sparrow but the young midfielder headed home in the 24th minute to give the Iron a comfortable cushion.
Huddersfield came back on the restart with a 46 minute goal from Andy Booth, but then came Fowler's dismissal which proved to be the catalyst for their demise.
The Iron took control as Terry Barwick (55) rammed home his first senior goal and then MacLean made it four in the 59th minute.
MacLean headed his second in the 68th, forced Ian Gray to tip another effort onto the bar and lob home his third and his 12th of the season, in the closing minutes.
In between Booth had grabbed a second for Huddersfield, but his sterling work was in vein.