Key figure in the Darlington defence was Matt Clarke who was a real colossus alongside skipper Neil Maddison, while Clyde Wijnhard's experience was invaluable.
Scunthorpe's Matt Sparrow had a sparkling game in midfield, but he lacked a lot of support while leading scorer Paul Hayes was left stranded after losing his strike partner Neil Teggart, after Butler's dismissal, to be replaced by defender Mark Jackson.
After a quiet opening Scunthorpe were first to show when Peter Beagrie crossed from the left and skipper Andy Crosby delivered the ball across the face of goal but Hayes just failed to connect.
Attack was matched by counter attack and Alun Armstrong's weak shot from the left failed to trouble Paul Musselwhite and Wijnhard then found space to drive a fierce shot wide.
Midfielder Richard Kell did well to retain his balance under a strong challenge to force Sam Russell into a smart save and then Butler forced in a header from Ian Baraclough's low cross but was off target.
The complexion of the game changed in the 37th minute when Scunthorpe's Butler was shown a straight red card by referee Scott Mathieson for a foul on the edge of the box on Maddison.
The resulting free-kick was taken by Wijnhard who hammed the ball through the wall and Musselwhite saved well with his legs.
Scunthorpe almost grabbed the lead when Crosby's free-kick was collected on the turn by Hayes who forced a fine save at the foot of the post by Russell.
Ian Baraclough was close with a free-kick as Scunthorpe fought desperately to gain the upper hand, but the game swung the Quakers way in the 61st minute when Armstrong was quick to react to Neil Wainwright's cross and stab home.
The 10-men Scunthorpe side were continually frustrated as their attempts to create attacking moves broke down, although the hard-working Sparrow tested Russell in the closing stages from the edge of the box.
With four minutes left Darlington were reduced to 10 men when Close saw red, following a second yellow card offence.