West Ham United made it a deadly dozen victories for the season as they blunted the rock-bottom Blades at London Stadium, to depart at the final whistle in the rarefied heights of fourth place.

After being denied an early spot-kick by another marginal VAR decision, skipper Declan Rice finally netted West Ham’s first penalty award of the season to claim his opening goal of the campaign, four minutes before the break.

And after Issa Diop doubled the lead when he glanced home Aaron Cresswell’s corner as the hour-mark approached, late substitute Ryan Fredericks cemented a clinically-efficient win with the last kick of the night.

With the Hammers following up their victory at Bramall Lane in November, sinking Sheffield United’s 19th defeat of the season means that they still need at least a draw to eclipse Derby County’s all-time Premier League low of 11 points.

Following last Tuesday’s FA Cup fifth-round, extra-time exit at Manchester United, David Moyes made a quartet of changes as Diop, Ben Johnson, Manuel Lanzini and Jesse Lingard came in for injured duo Angelo Ogbonna (ankle) and Andriy Yarmolenko (knee) plus substitutes Pablo Fornals and Mark Noble.

Despite kicking off in 20th-spot - 14 places and 28 points adrift of the Hammers - Chris Wilder’s men had arrived in the capital having enjoyed a slight upturn in fortunes after winning six of their last nine matches in all competitions.

That included their FA Cup fifth round victory over Bristol City last Wednesday but that brief resurgence from a side that had come into the New Year with just two points on the board, counted for nothing against Moyes high-flying Hammers.

The Blades boss made still made three changes from the team that had reached those FA Cup quarter-finals as Oliver Norwood, Ben Osborn and Enda Stevens were recalled at the expense of John Fleck plus substitutes Max Lowe and Rhian Brewster.

And with four minutes on the clock, Stevens had a huge let-off, when he unceremoniously upended Craig Dawson as the pair raced in pursuit of the loose ball after Declan Rice’s stinging, low 20-yard free-kick was only parried by Aaron Ramsdale.

But as the Hammers skipper then waited an eternity to take the Hammers first penalty kick of the campaign, referee Simon Hooper gave Rice the dreaded signal that VAR had spotted a marginal offside against Dawson and the Blades survived an early scare.

Although the visitors forced a couple of corners, the Hammers with Jarrod Bowen playing furthest forward looked most dangerous and, as the quarter-hour mark approached, Lingard’s incisive run set up Lanzini but once again Ramsdale parried, somewhat unconvincingly, to safety.

Midway through the half, Lingard escaped, once more, and this time the Blades ‘keeper looked more assured as he steered the on-loan Manchester United star’s angled scorcher around his near-post for West Ham’s first corner of the evening but Dawson subsequently nodded Cresswell’s flag-kick over the bar.

On the half-hour mark, it was Cresswell’s turn to curl a 20-yard free-kick onto the canvases protecting the Sir Trevor Brooking Stand seats after Egan crudely upended Bowen, while at the other end, the alert Łukasz Fabiański got down to claim Stevens’ low cross as Billy Sharp raced in for the kill.

Osborn then forced the Polish ‘keeper to divert his low 25-yarder around the base of his left-hand upright, as the Blades enjoyed their most threatening spell of the opening period but in pushing too far forward, they left themselves far too open at the back.

With Norwood’s sloppy ball being intercepted in the Hammers half, Bowen and Lanzini broke upfield alongside Lingard and, with the consequently-cautioned Chris Basham finding that the only way to stop the three Claret and Blue musketeers was to launch himself into the back of the boy borrowed from Old Trafford as he shaped to shoot, the only possible outcome was a penalty.

Without hesitation, Referee Hooper again pointed to the spot and with no VAR intervening this time, the only thing that was going to stop Rice from taking the penalty was Lingard, who having now dusted himself down, made an impassioned plea for the ball.

Captain Rice, however, held firm and duly despatched his penalty beyond the outstretched right glove of Ramsdale and into the bottom left-hand corner to bag a long-overdue first goal of the campaign, while the Hammers claimed an interval lead.

Seven minutes into the second half, Sharp’s cross into six-yard box was met by McGoldrick, whose header hit Johnson on the shoulder before being tipped over the top by Fabiański and, indeed, that would prove to be a huge turning point.

On 58 minutes, Lanzini released Bowen into the six-yard box, where the tenacious No.20 saw his shot deflected behind for a corner, which Cresswell curled into the danger-zone for Diop to ghost in front of marker Ethan Ampadu and head home.

With the deficit now doubled, Wilder introduced Oli McBurnie as Norwood stood down, before Moyes sent on Noble in place of Lanzini and, after Lingard’s low 25-yarder was held by Ramsdale, Fabiański produced another brilliant reaction save to hold McGoldrick’s point-blank header at the second attempt.

Desperate for a goal on his home debut, Lingard forced Ramsdale to tip his steaming 20-yarder aside for a corner as it scorched through cold Stratford air and then the advancing Vladimír Coufal found himself in unfamiliar territory but with only the Blades ‘keeper to beat, his stinging shot was parried for another flag-kick.

The match now beyond them, the night got yet worse for struggling Sheffield United, when Egan was stretchered away after bravely blocking Lingard’s shot.

Then, in the sixth-minute of stoppage time, the recently-arrived Saïd Benrahma combined with fellow substitute Fredericks, who left Ramsdale groping at thin air, when he steered a low 18-yarder into the bottom left-hand corner to leave the Hammers in both fourth-spot and confident mood ahead of Sunday lunchtime’s visit of Tottenham Hotspur.

West Ham United: Fabiański, Coufal, Johnson (Fredericks 90+1), Cresswell, Dawson, Diop, Rice, Souček, Bowen, Lanzini (Noble 63), Lingard (Benrahma 82).

Unused Subs: Martin, Alves, Fornals, Odubeko, Coventry, Baptiste.

Sheffield United: Ramsdale, Basham, Egan (Jagielka 85), Stevens, Ampadu, Lundstram, Norwood (McBurnie 62), Bogle, Osborn, McGoldrick, Sharp.

Unused subs: Foderingham, Baldock, Lowe, Burke, Brewster, Bryan, Maguire.

Booked: Basham (39), Lundstram (87)

Referee: Simon Hooper