Hughes, recalled to the starting line-up for the first time in two months, rescued County's unbeaten away league record, which is now 18 games stretching back to February.
"I felt it was the right time to bring Lee back in," said Curle. "I know his character and I know if you put him in at the right time and against the right opposition, then you will get goals out of him."
"I wish I could say it was because of what he had been doing in training - but he has just had a few days off!"
Curle added: "I thought some of our football was excellent but I am really disappointed with the goals we conceded. We have come here and adjusted our system to stop Scunthorpe playing, but have then gifted them two goals.
"We should have done much better with our defending out wide for each goal. It really annoys me because we spend so much time working at our defending on the training ground."