The opening ten minutes saw the Blades as the more dangerous of the two teams, as they saw more of the ball but came up against a resolute back line.
Whichever side had won the game would have climbed into the top half of the table, but it was the visitors who took the spoils.
And, as in the FA Cup game earlier in the season, a Chris Porter penalty in the last ten minutes saw the Blades grab victory.
The match was one that lacked many clear cut chances and it remained in the balance right until the dying stages.
The U's were left to rue a late goal for the second game in a row as Sheffield United grabbed a late winner for their sixth successive victory.
With the U’s playing a narrow four in midfield, the Sheffield full backs were seeing plenty of the ball, but Walker remained untested in the opening quarter of an hour.
The U’s first chance of the game came just before the twenty minute mark. Some good approach play saw them get Sears just in behind the Blades back line and his hooked effort with his back to goal dropped just wide.
Whilst the Blades were moving the ball around with some purpose and getting into wide areas, chances remained at a premium in what was a quiet first half.
Tom Eastman was in the right place at the right time on the half hour mark, though, to block a Harris shot after a slip up at the back.
He almost scored at the other end from a corner as two set pieces caused problems at the back for the visiting defence.
Dickson became the first player to go into the book five minutes before half time for bringing down Davies as he ventured into the U’s half on a counter.
Davies then almost got on the end of a dangerous left hand cross as the visitors finished the half the stronger.
But the U’s got to half time without conceding and then made two changes at the interval as Alie Sesay made his Football League debut as he came on for Brian Wilson and Craig Eastmond came on for Clinton Morrison.
Straight away, there was more tempo to the U’s play, although Eastman again had to be in the right place at the right time to block a Maguire run and shot as he entered the home penalty area.
The U’s hit the Blades on the counter on 54 minutes as Sears and Vose got away at pace, but Sears’ pass was just too heavy for the run of Ibehre.
Sesay got forward with purpose on the hour mark, sending over a looping cross that Howard collected at the second time of asking under pressure from Ibehre.
At the other end, the Leicester loanee saw Baxter skip inside him to curl in a low shot that beat the dive of Walker but came back off the foot of the post.
The Blades were having the better of the game at this juncture and Murphy lifted a shot just wide under pressure from Walker.
Eastman gave the ball away to Murphy but recovered to block the ball as the striker eventually got his shot off.
The match was fired up by the referee’s interventions that annoyed the U’s supporters and management alike.
Chances remained at a premium, but Walker pulled off a superb stop to deny Murphy from close range.
And although Ibehre flashed a header wide of goal in injury time, the Blades back line protected Howard until the final whistle to ensure the points went to Yorkshire.
Like in the FA Cup game, the Blades got their noses in front late on in the game as the U’s conceded a penalty. Sears caught Davies as he cut back inside and Porter smacked home the spot kick.