Bradley Johnson netted the only goal of the game after capitalising on a mistake by full-back Stephen Jordan who missed timed a clearance to allow Robert Snodgrass to race clear and cut the ball back to the midfielder who fired home; with just seven minutes remaining.
From there the game turned ugly when either side were reduced to ten men after seeing their respected substitutes sent off for different offences.
Firstly Scottish winger Robert Snodgrass, who had replaced Lloyd Sam on the hour was handed two yellow cards before a dangerous lunge from Jamie Ward resulted in a straight red card.
Blades boss Gary Speed had made changes prior to the game, giving a start to Stephen Quinn in a squad which included new signings Richard Wright and Ritchie de Laet on the substitute's bench.
It was the visitors who started off the brightest; opting for an all black away kit the Blades lead the possession early on, attacking without prevail straight from kick-off. But as the game went on it was Leeds who slowly took hold of the game.
Opportunities in front of goal were too few and far between with Ched Evans firing a brace of free-kicks into the wall before towards the end Stephen Quinn curled into the top corner for keeper Shane Higgs to save.
In the United goal Steve Simonsen commanded well and made the save of the game when he picked out Bradley Johnson's header - pushing out for a corner. And in much controversy the referee awarded Leeds with a penalty after an alleged handball from Kyle Bartley; however his assistant came to the Blades rescue who confirmed that the handball came from a white shirt.
At half-time on loan Manchester United defender Ritchie de Laet was handed his Sheffield United debut; replacing Jean Calvé at right full-back.
For the Blades the second half was more fruitful as they claimed more possession and began to make headways in front of goal, but the visitors lacked that killer instinct which was more than matched by a strong Leeds defence.
Robert Snodgrass entered the field on the hour mark and it wasn't long before the referee was writing his name in his book; he was booked for unsporting behaviour after failing to allow united take a free-kick.
With seven minutes remaining of the game it was the home side who struck the decisive blow, a long clearance was mistimed by left full-back Stephen Jordan who let Snodgrass run clear and square the ball across goal to a pouncing Johnson who fired home past Nyron Nosworthy on the goal line.
The Blades hushed and hurried but was unable to find the back of the net, Leeds were reduced to ten men after Snodgrass was shown a second yellow card and moments later Jamie Ward was handed a red.
In the dying minutes a Johnny Ertl header found the cross bar with Richard Cresswell unable to match the rebound as Higgs saved comfortably.
It wasn't an inspiring performance by the Blades but neither the less was not one which deserved a defeat, they travel to Nottingham Forest on Tuesday night hoping to pick up three points on the road.