Manchester City were dominant throughout most of the match, and whilst their attacking players were not at their best, their defence flourished, with the centre-back pairing of Ruben Dias and John Stones starring in particular.
This was a sign of the change that City have undertaken over the course of this season, shifting from their free-flowing attacking style of play, to one that is much more solid defensively, focusing on utilising areas of their game that they normally refrained from using in the past, such as set-pieces.
City scored both of their goals against United from set-pieces, with Stones and Fernandinho both scoring after losing their man-marker in the United box.
Pep Guardiola's new style of play has seen City change from last season, from scoring 43 goals in 15 Premier League games last season, to just 24 this season, the lowest in the league's top 10.
However, defensively they have been brilliant, conceding just 13 goals in the league so far this season, whilst last season they conceded 17 goals in 15 games.
Additionally, City are in a fine string of form right now, going 12 games unbeaten in all competitions, and during that time, they have scored 24 goals in those games, conceding just three goals in the process.
This has been helped by the signing of Dias from Benfica this summer for €68 million, who has also helped potentially revive John Stones's career at City, who was set to leave the club in the summer, especially with the signing of the Portuguese international.
The pair's excellent form has seen them displace Aymeric Laporte completely, who was normally the standout centre-back under Guardiola, yet his career has been hampered by injures. The difference this time is that he is fully fit, but the impressive performances from Dias and Stones have kept him out of the side.
Dias made two crucial blocks against United, and Stones scored the opening goal that drove City on for the win on Wednesday, and there is surely more to come from the pair.
If City win their two games in hand in the Premier League, they will be two points clear of current leaders Liverpool.
Man City might have dropped off when it comes to goals from previous seasons, but Guardiola has managed to adapt to the circumstances, having to play without Sergio Aguero and Gabriel Jesus in numerous games, yet he is still getting the results he wants.