Skipper Billy Sharp scored United's final goal of a successful pre-season campaign.
A 2-0 success at Doncaster Rovers on Friday night saw United end preparations with four wins and two draw.
Sharp benefitted from a pass from newboy David McGoldrick, who added the first at the Keepmoat, as United scored twice in the last 20 minutes.
"I like to come back to Doncaster, I was waiting for one chance," said Sharp. "David played a ball through and I managed to finish it off. It was nice to get a goal and 90 minutes, I felt stronger as the game went on, we got stronger as a team in the second half.
"More importantly we collected a clean sheet and a win, the gaffer will be pleased with that but we start for real next week, and we need to be at it from the off.
"The gaffer has shared the minutes out, he has talked about opportunities and it is up to him to pick a team now for the Swansea game."