Liverpool’s latest title challenge has begun in formidable and often near flawless fashion but their seventh successive Premier League win came riddled with imperfections, reminding everyone that they are mortal after all.

A week after winning at Everton, Sheffield United revelled in going toe to toe with the European champions and seemed set to collect a point before a ghastly, freakish, goalkeeping error on the part of the previously underemployed Dean Henderson gifted Gini Wijnaldum the winning goal. It was Liverpool’s first victory here since 1990 and they are unlikely to forget it in a hurry.

Sheffield United 0-1 Liverpool: Premier League – as it happened Read more

Along the way Jürgen Klopp was forced to make changes to formation and personnel as his side struggled to preserve their 100% League record. “Had it been a draw I would have said it was what both teams deserved,” he said. “It is unlucky for Sheffield United, for sure.

“We were playing against a proper unit with the team, the manager and the crowd all making it feel as if you were playing against a wall. I was very impressed. The way they fight and play reminded me of my old team at Mainz. They do so many really good little things.”

If Liverpool had expected Sheffield United’s overlapping centre-halves to retreat into their shells, they were swiftly disabused as Jack O’Connell, the left-sided element of the defensive trinity, pressed forward and Enda Stevens, the left wing-back, repeatedly accelerated into the space left behind Trent Alexander-Arnold. While Chris Wilder had clearly identified Liverpool’s right-back as a weak defensive link, Stevens shone.

As a former centre-half, the watching Gareth Southgate probably enjoyed the no-quarter-given duel involving Oli McBurnie – whose bristling ginger beard seems somehow emblematic of his invariably feisty interpretation of the centre-forward role – and Virgil van Dijk. Although the much lauded centre-half held his own, he will certainly have had more comfortable afternoons.

Southgate had driven down from his North Yorkshire home to watch contenders for his England squad, perhaps including George Baldock, Sheffield United’s right wing-back whose private duel with Andy Robertson would assume increasing importance. It did not take long to realise that, like Alexander-Arnold, Robertson could not exert his usual influence.

Facebook Twitter Pinterest Wijnaldum’s shot squeezes through Henderson’s legs. Photograph: Laurence Griffiths/Getty Images

Although Liverpool dominated possession, the home side counterattacked cleverly. Only Joël Matip’s interception kept McBurnie at bay and Callum Robinson missed a couple of chances as Liverpool struggled for fluency.

So assiduous was the pressing and closing down that, at times, it looked as if Sheffield United contained two or three more players. With almost their every manoeuvre second guessed, Liverpool seemed in peril of suffocation and when Sadio Mané did finally break free he was halted by the most courageous of challenges from John Egan. The Irish centre-half had a lot to do with the lack of visiting shots on target, not to mention the way Mané and Mohamed Salah found themselves repeatedly, and unceremoniously, shunted down attacking cul-de-sacs.

Admittedly Mané’s strike did rebound off a post as the ball bagatelled around the home area. It was characteristically cleared before Roberto Firmino could redirect the fall out beyond Henderson. Starved of time and space, Liverpool began snatching at the ball. Shots were sliced, passes overhit and crosses skewed as they struggled to cope with the success in subduing their full-backs.

Klopp started pressing assorted tactical buttons, Alexander-Arnold and Robertson swapped flanks, Jordan Henderson was replaced by Divock Origi, the formation switched to 4-2-4 and the battle of the flanks heightened.

Yet amid the danger, McBurnie drew a good save from Adrián while only Van Dijk’s interception came between John Lundstram and a goal.

The Fiver: sign up and get our daily football email.

No one guessed calamity of the cruellest order beckoned for Henderson. For much of the afternoon Wijnaldum’s performance had been regressively reminiscent of his once routinely ineffective away displays at Newcastle but then the Dutchman met a headed clearance on the edge of the area and volleyed straight at Henderson.

The keeper looked to have gathered routinely only for the ball slip from his fingers and through his legs before it slowly, agonisingly trickled across the line.

Henderson stood alone, head in hands, and as if in sympathy, the sunshine briefly illuminating Bramall Lane was replaced by more of the rain that had earlier soaked the city.

Henderson would soon save superbly from Salah but his manager clearly did not regard it as redemption. “We’ve had a golden opportunity,” said Wilder. “And we’ve let it slip through our hands.”