The Frenchman completed 78 minutes on his comeback from a knee injury at Bramall Lane, where Sergio Aguero came off the bench to net the match winner, tapping home Kevin De Bruyne’s precise cross from inside the six-yard box.
It was a moment of relief for City, who saw Gabriel Jesus' penalty saved by the impressive Dean Henderson in the first half of a keenly fought contest.
Aguero’s goal, his eighth in five games, deservedly rewarded the visitors’ attacking endeavour against a stubborn Blades’ defence, as we stretched our unbeaten run to seven matches and move six points clear of third placed Leicester City.
The Yorkshire club’s home form and water-tight back line has been the cornerstone of their impressive return to the top tier and it was evident here, as Chris Wilder’s side made City work hard for the three points.
There was a sense of relief when Aguero scored, but it might not have been the case but for an inspired performance from Henderson.
The England U21 produced a stunning one-handed save to deny Raheem Sterling from six-yards and stopped from a similar distance in the next passage of play to keep out Nicolas Otamendi’s scissor-kick.
He saved his best for Jesus’ penalty, awarded when Chris Basham cleaned out Riyad Mahrez after the Algerian’s footwork confounded John Egan and Enda Stevens.
The Brazilian took responsibility in Aguero’s absence, but his effort was a perfect height for Henderson, who correctly guessed left and pushed the ball away to safety.
United had offered little in a first half in which they failed to register a shot on target, but had two glorious chances to take a surprise lead after the break.
Rodrigo had sent a looping header inches wide of the right post as City continued to huff and puff in attack, before Ederson failed to gather Basham’s cross-cum-shot only for Lys Mousset to back-heel straight at the keeper when he might have teed John Fleck who was waiting to smash home.
It was a reminder of how finely the game was balanced, and City hearts were left racing again when the unmarked Oli McBurnie slid in but failed to connect with Stevens’ teasing ball across the face of goal.
It was the host’s best move of the game but a minute later, Aguero netted the decisive goal in what was almost a carbon copy of McBurnie’s missed chance.
De Bruyne’s pass from the right proved more precise than Stevens, leaving the Argentine ace with the simplest of finishes.
The weight visibly lifted from City, who played with more freedom in the closing stages, when Sterling went close to doubling the lead with a shot that went just wide of Henderson’s left post.
A free-kick in the dying minutes of added time asked questions of our defence as United packed the box, but we remained resolute to see out the game.
Laporte was the story of the night as he made a welcome return from a long-term knee injury at the heart of the City defence.
It was a steady performance from the Frenchman, who was a reassuring presence in this, his first game in 143 days.
An early misplaced pass was evidence of the rustiness you would expect and almost allowed the hosts a shooting opportunity, but moments later, after surviving a clattering late challenge from Mo Besic, Laporte flew into a sliding tackle to remind everyone of his defensive prowess.
He did even better later on, heading clear on the goal line under pressure from several red shirts after a corner evaded Ederson.
There will be tougher tests ahead, but a clean sheet on his return is a job well done.
And how good was it seeing him back in sky blue!?
"We knew it would be a difficult place to come. We concede one or two clear chances, nothing more than that.
"In the first-half the keeper was excellent with the penalty and two incredible saves, it was an incredibly good victory for us to take a step towards securing Champions League football next season."
Man of the Match – Kevin De Bruyne
This wasn’t City at our best and Wilder’s side made life difficult, but at the heart of everything good was our Belgian maestro, whose ability is equally matched with a tireless work rate.
Another wonderful assist unlocked a stern defence for us to pick up an important three points.
De Bruyne is the first player in Premier League history to provide 15+ assists in three different campaigns.
What it means
Our eighth away win of the season means we are now unbeaten in five consecutive Premier League games and remain second in the Premier League table with 51 points from 24 games.
This win moves us six points clear of third-placed Leicester City, who face West Ham on Wednesday and leaves us 13 points behind leaders Liverpool, who play Wolves on Thursday.
We return to the Etihad Stadium on Sunday for an FA Cup fourth round tie against high-flying Championship outfit, Fulham. Kick-off is at 13:00 (UK) and we’ll have live updates here on mancity.com.