Just as at Tottenham on Thursday it was Timo Werner who was fouled, and this time Jorginho opted for his more traditional spot-kick technique to send Aaron Ramsdale the wrong way. He is now our second top goalscorer in the league with five.

That 58th-minute winner came very soon after Toni Rudiger had awkwardly put through his own net for what was an unfortunate first goal conceded under Thomas Tuchel. The German more than made up for that mistake with a series of crucial blocks and clearances as we doggedly defended our narrow lead late on.

We had enjoyed a couple of let-offs early in the game, not least when a penalty awarded to the Blades was overturned because of a tight offside in the build-up. We grew into the contest, though, and with the half-time whistle approaching Mason Mount fired us in front after great work from Werner.

As expected against a team fighting for their lives at the bottom of the table and who are always in games, it was a battle throughout with the Blues never entirely comfortable, but a 96th-minute Edouard Mendy save from a Billy Sharp overhead kick got us over the line.

Chelsea move to within a point of fourth-placed Liverpool on the back of a third straight victory.

The Selection

Tuchel made three changes to the Chelsea team that started at Spurs, bringing in Andreas Christensen, Ben Chilwell and Olivier Giroud. Christensen replaced the injured Thiago Silva, Marcos Alonso made way for Chilwell and Giroud lead the line with Callum Hudson-Odoi dropping to the bench. Werner and Mount played off him.

There was no Christian Pulisic in the squad for personal reasons, but Kurt Zouma returned to the bench after injury, and Billy Gilmour was in the matchday squad for the first time under Tuchel.

Early escapes

Precisely 30 seconds was all it took for our run of three straight clean sheets to almost come crashing to an end. Oliver Burke was slipped clear by his strike partner Oli McBurnie after we had lost possession in midfield, but thankfully his effort flew into Mendy’s side-netting and not the goal.

We responded by winning a couple of corners which amounted to nothing, but then did quickly create a clear opening of our own. Mateo Kovacic fed an inviting pass over the top which Werner reached before Aaron Ramsdale, and while he lofted the ball past the keeper it had neither the pace to reach the goal, nor the lurking Mount, with Chris Basham in the right place to clear.

The ever-present Blade’s next involvement, on 12 minutes, was to be brought down by Chilwell inside the box. The referee deliberated before pointing to the spot, and there was a further wait for a VAR check. That confirmed Basham was marginally offside when the initial cross came in.

Basham was then booked for bringing down Werner as the contest ended a scrappy stage on a bitterly cold night in South Yorkshire. We were struggling to control possession and tempo in the manner we had done on Thursday, with the energetic Blades pressing us back and forcing errors.

Getting ahead

But we rode out the tricky spell and, with the interval approaching, clinically converted a well-worked move.

Chilwell slipped a pass into the inside-left channel for Werner, ever the willing runner, and his centre was intelligently placed behind the Blades’ retreating backline to Mount. Coming at speed it was not an easy first-time finish but Mount certainly made it look that, planting his left-footed shot into the corner.

It was the perfect way for the midfielder to answer his new boss’s request for more efficiency in front of goal!

The final three minutes of the first half passed without incident, as did the opening stages of the second. The game then burst into life, with two goals in four minutes.

Action at both ends

The first was a horrible one to concede from our perspective. McBurnie tried to slip Burke through but Rudiger got across to cover. Mendy came out of his goal to collect at the exact moment the German passed it back to him. It wrongfooted the keeper and rolled agonisingly into the unguarded net.

We didn’t dwell on a first concession under Tuchel for long. In fact, only 70 seconds had elapsed when Werner intercepted a short Jayden Bogle back-pass and knocked it around Ramsdale, who could only bring him down.

It looked a penalty, but the on-field refereeing team said no. After quite a wait with the ball still in play, Kevin Friend was advised to check the pitchside monitor by his colleagues at Stockley Park. He changed his decision.

The seventh penalty won by Werner this season was coolly converted by Jorginho, who reverted to his hop-skip-and-a-jump technique. He sent Ramsdale the wrong way.

Shortly after the hour, Tuchel shuffled his pack, bringing on Hudson-Odoi and Alonso for Giroud and Chilwell. N’Golo Kante for Werner was our final sub as our shape shifted to 3-5-2 for the last 15 minutes, Mount and Hudson-Odoi operating in false nine roles.

Before then, Rudiger atoned for his error with a fantastic covering header to clear a threatening free-kick, and then a brave block to stop John Fleck’s shot troubling Mendy after he had danced through our defensive block.

Digging in

With the clock running down, Rudiger blocked expertly again in five minutes of injury time, and in the last of those, Mendy got down low to parry a Billy Sharp overhead kick that was destined for the corner.

It was the last action of a tense and tight encounter in which Tuchel’s side showcased their ability to grind out a victory once more.

What's next?

The Blues are back in South Yorkshire on Thursday night with Barnsley awaiting in the fifth round of the FA Cup. Our next league game is at home to Newcastle a week on Monday.

Chelsea (3-4-1-2): Mendy; Azpilicueta (c), Christensen, Rudiger; James, Jorginho, Kovacic, Chilwell (Alonso 62); Mount, Werner (Kante 75); Giroud (Hudson-Odoi 62).Unused subs Kepa, Zouma, Emerson, Kante, Gilmour, Ziyech, Abraham.Scorers: Mount 43, Jorginho 58 (pen)Booked: Basham 17

Sheffield United (3-5-2): Ramsdale; Basham, Egan, Bryan (Sharp 68); Lowe, Lundstram, Norwood (Brewster 86), Fleck, Bogle; McBurnie, Burke (McGoldrick 62).Unused subs Foderingham, Jagielka, Osborn.Scorer: Rudiger OG (54)

Referee Kevin Friend