A stoppage-time goal cruelly denied the Blades a place in the top six of the Sky Bet Championship, despite dominating against second placed Cardiff City.
Leon Clarke put United in the ascendency and Chris Wilder's side more than deserved to win the game, only for Anthony Pilkington to snatch a last-gasp leveller against the run of play.
Welsh international midfielders Evans and Brooks were handed starts, whilst Moore replaced the suspended Blackman in goal. Leonard and Sharp dropped to the bench, with Clarke taking over the captain's armband.
At a soggy Lane, United almost struck first in fortuitous circumstances, when Bennett's headed hit Grujic and almost wrong-footed Etheridge. United continued to press forward and following a quick break involving Baldock, Clark and Brooks, Evans fired over from a promising position. In response, Grujic fired an effort goalwards, it was deflected by Zohore, but he adjudged to be in an offside position.
In the 28th minute, the Blades did deservedly go ahead. Evans and Lundstram exchanged passes on the edge of the penalty area, before the latter fed CLARKE and he effort deflected off his marker and beat a tumbling Etheridge. Bennett then saw yellow for a cynical foul on Basham, as he attempted to launch a counter attack.
The home faithful were in full voice and were almost rewarded with a second. Clarke played Stevens behind Mendez-Laing and his cross was inches away from Brooks and then Baldock. With half-time approaching, Stearman rose highest at the back post from a corner, but his header was cleared off the line by Bennett.
One minute of added time was signalled and the Blades continued to push forward, with Lundstram firing wide of the target after being teed up by goalscorer Clarke.
Before the restart, Madine replaced Mendez-Laing. Like much of the first period, the second began at a frantic pass and only a last-ditch tackle from Etheridge denied Evans, after the Welsh international had been played through by Fleck. At the other end, City threatened themselves. In the second phase, Gunnarsson broke clear down the right and fizzed an effort inches wide of the target.
City were now more of attacking threat, with Moore at his best to deny Zohore at his near post. From the resulting corner though, United broke and Lundstram fired over from the edge of the area, after Baldock found himself United's most advanced player.
With 21 minutes remaining, United were forced into a change, with Wright replacing the injured Stearman. Back to the action, Fleck overlapped down the left and stung the palms of Etheridge. A second change followed, with Brooks being replaced by Donaldson.
The Blades came oh so close to a second as they caught Cardiff cold from a set-piece. Fleck freed Stevens with Manga and Morrison not facing play and Donaldson slid in at the near post, only to see the woodwork deny him with Etheridge beaten.
A flurry of corners went the Blades way, before appeals from the Kop for a penalty were waved away as Bamba appeared to foul Evans. Again, from a Stevens cross, only a crucial block from Etheridge denied the Blades, with Clarke unfortunate not to get a second.
Four minutes of added time were signalled and Cardiff broke Blades hearts in the first of those as the grabbed an undeserved equaliser. A lump forward was headed on twice, before PILKINGTON volleyed home from inside the box to snatch an unlikely point.
Blades: Moore, Baldock, Stevens, Fleck, O'Connell, Basham, Lundstram, Clarke, Stearman (Wright 69), L. Evans (Leonard 88), Brooks (Donaldson 71).
Unused: Sharp, Lafferty, Holmes, Eastwood.
Cardiff: Etheridge, Bennett, Morrison, Manga, Zohore (Pilkington 78), Bamba, Gunnarsson, Paterson, Mendez-Laing (Madine 45), Grujic, Hoilett (Wildschut 78).
Unused: Peltier, Bryson, Murphy, Ward.