Manchester City were on the right side of some contentious decisions as Sergio Aguero's controversial goal and a late Kevin De Bruyne effort earned a 2-0 win over Sheffield United, Pep Guardiola's 100th in the Premier League.
With leaders Liverpool having extended the gap at the top with a win over Wolves, City were fortunate not to fall behind in the first half when Lys Mousset had a goal harshly disallowed by VAR.
However, there was more controversy to follow, with the visitors incensed after referee Chris Kavanagh failed to stop the play despite accidentally blocking off John Fleck in the build-up to Sergio Aguero's opener.
VAR did come to the Blades' assistance when it deemed John Egan had not deliberately handled a Riyad Mahrez shot, though City had the points wrapped up when De Bruyne lashed in with eight minutes remaining, as Guardiola reached 100 wins in 134 matches to break Jose Mourinho's record.
With Mousset having squandered an early header, United thought they had the lead when the striker kept his cool to slot beyond Claudio Bravo, who was starting in place of the suspended Ederson, only for VAR to disallow the goal for a marginal offside call.
Mousset got the better of City's defence again prior to half-time, yet sliced his effort into the side-netting after latching onto Oliver Norwood's pass.
Despite their poor display, City took the lead six minutes into the second half - Aguero clinically drilling in his 10th league goal of the season.
United were adamant the goal should not have stood due to the referee's accidental interference, but VAR once more went against them.
City then wanted a penalty when Egan blocked Mahrez's shot, though their claims were rejected despite the ball hitting the defender's arm.
Any hopes of a comeback were ended soon after as De Bruyne calmly swept home, though Billy Sharp went agonisingly close to setting up a grandstand finish with a looping header which hit the upright and rolled across the line as United's unbeaten run on the road came to an end at nine.
What does it mean? City give themselves breathing room
With Liverpool so far ahead, the title race seems all but over, though City could have been looking over their shoulder had they failed to win, with Chelsea coming from behind to beat Arsenal earlier on Sunday.
As it is, the champions have restored the six-point gap between themselves and Frank Lampard's side, though they still sit a point behind Leicester City in second.
Aguero rediscovers his home comforts
It was a far from a vintage all-round display from Aguero, but when he was put through by De Bruyne's pass, he never looked likely to fluff his lines to score his first home league goal since November 2.
City's ramshackle defence get lucky thanks to VAR
Hindered by a lack of options, Guardiola handed a first Premier League start to 18-year-old Eric Garcia, though the youngster - alongside Fernandinho - was often caught out by the pace of Mousset and the speed of United's counters.
Indeed, only a marginal offside decision sparred City's blushes. They will surely look to bring in defensive reinforcements in January.
Key Opta Facts
- City are unbeaten in their past 38 Premier League home games against promoted sides (W34 D4) since a 2-0 loss against Reading in February 2007. Only Chelsea (43 games between 2001-2015) and Manchester United (40 games between 2002-2015) have had longer such runs in the competition.
- Aguero has scored against 32 of the 33 opponents he has faced in the Premier League, with Bolton Wanderers being the only team he has failed to net against (one appearance).
- Aguero has scored 22 goals for City in the Premier League in 2019 - only in 2016 has he scored more in the competition within a calendar year (27).
- Bruyne has been directly involved in 19 goals for City in the league this season (seven goals and 12 assists) - only Leicester's Jamie Vardy has had a hand in more (20).
- The Belgian has made an assist in each of his past three Premier League games. Of the four instances of a player assisting in three or more consecutive Premier League appearances this season, half of them have been by De Bruyne.
Carlo Ancelotti's Everton visit the Etihad Stadium on New Year's Day, while the Blades visit runaway leaders Liverpool on Thursday.