The Blades looked stronger in defence and attack although Rovers took the honours with their creative approach work which fell apart close to goal.
Billy Sharp had an angled shot comfortably saved in the eighth minute, before Darren Byfield hit a fierce effort wide four minutes later after good work from Jason Price and Richie Wellens.
Doncaster were out of luck when they gave the opposition the lead with an own goal for the second match in a row.
There was little danger when Danny Webber crossed the ball from the left in the 14th minute, but Gareth Roberts hammered the ball into his own net in a hasty attempt to clear.
Rovers piled on the pressure for the rest of the half in a determined bid for an equaliser but their efforts were in vain.
Byfield was unable to turn a terrific header from Matt Mills into the net following a 19th minute corner and Brian Stock was unlucky to rattle the crossbar with a fierce effort after dribbling through the middle in the 24th minute.
Price was put clean through by Martin Woods five minutes later, but his low shot was saved by keeper Paddy Kenny's legs.
Rovers had no luck at all, but Woods should have done better when he fired wide in the 33rd minute, before James Beattie headed a good chance off the mark following a rare opportunity at the other end.
United's second goal came in the 60th minute when the lively Stephen Quinn took a pass from Beattie in his stride and slotted the ball home in fine style.
Mark Wilson had a fierce angled effort tipped away by Kenny when Rovers tried to reply a couple of minutes later.
But it was just not to be for the home side and their misery was complete when Byfield skied a gift opportunity over the bar from close range, following a mistake by Gary Naysmith in injury time.