Alan Knill was critical after referee Gary Sutton sent off Mark Duffy before Scunthorpe slumped to a 0-0 draw at fellow strugglers Bury.
Knill was left frustrated by Sutton's decision, which saw Duffy given his marching orders in the 31st minute for a challenge on Patrick Cregg.
But the former Bury boss still relished his players' performance in his first return to Gigg Lane since taking the Scunthorpe job almost a year ago.
"We never saw the red card incident and the ref seems to be the only person who did," Knill said. "Speaking to everyone, they thought it was soft. I think everyone was shocked when he pulled the red card out - it's one of those again.
"We're unbeaten this month despite another game when we were down to 10 men. We're quite well drilled in it now. We know exactly what we're doing and the shape is strong and compact so it forces the opposition to go long. We look tough to beat and credit to the players because it's been an unbelievable month.
"I'm glad it's the last midweek game. We've got plenty of tired legs and bodies but the effort is there for everyone to see. From where we were to where we are now is a vast difference."
