The Iron were undone by two second-half goals from Marlon Harewood, on loan at Barnsley from Blackpool, rendering Michael Collins' late strike as no more than a consolation.
“We’ve lost a game which I thought, if we’d taken it by the scruff of the neck in the first half, we could have come out of as victors,” said Baraclough.
“The first half set the tone for me. I thought we could have stamped our authority if we’d got tighter to people and if our passing had been brighter. That wasn’t good enough
“Barnsley showed a little bit more urgency to close the ball down and we gave them time to pass the ball. We made them look an excellent side at times. It was an evenly matched game but they showed more urgency.
“You can’t waste opportunities like this. It was a good chance to impose ourselves on Barnsley and we had the armoury to beat them.
“The results haven’t gone for us and that makes it doubly hard because now we have to go and get a result against Leicester at home on Saturday.”
The Tykes boss Mark Robins was pleased with the result, putting further space between his side and the relegation zone.
“I thought we controlled the game for most of it. Scunthorpe decided to sit in and try and make it difficult for us to break them down, which they did well. Then we got a bit of a rub of the green," he said.