Callum Harriott's early strike was enough to earn the visitors their eighth away win of the season at the John Smith's Stadium, to take them up to 12th while Huddersfield are just five points above the drop zone.
Town were on a high following their midweek win over Middlesbrough, when two late goals earned them a 2-1 win, but for Robins the result was a real kick in the teeth.
"What a difference a couple of days make," he said. "We were brilliant on Tuesday but we have been undone by a set-play.
"It feels like a step forward then two back but we have to take these on the chin I am afraid.
"We've not had enough quality. We have had plenty of ball in their box and although the way we got it there wasn't ideal, needs must at times."