After a 24 delay following a thunderstorm just before kick-off forced the game to be postponed this tie finally took place, although not before a little animosity between the two clubs following City's refusal to countenance a 6.00pm kick-off which the German's had requested so they could fly back home straight after they game. The host's said this was too soon to provide an adequate number of stewards.
Borussia originally brought around 1,600 supporters to the game, the majority of whom had to return after the game, meaning there was only some 500 travelling support in attendance.
However, by the end of the first half they probably wished they had gone home the day before as City eased into a two goal lead by half-time. Sergio Aguero anticipated Aleksander Kolarov's cross to open the scoring at the near post after just 8 minutes.
Ilkay Gündogan then had an effort saved following a swift City break and Raheem Sterling saw a goal-bound shot blocked as the home side dominated.
City doubled their advantage on 27 minutes when Borussia defender Christoph Kramer conceded a penalty in bringing down Gundogan. Aguero stepped up to send keeper Yann Sommer the wrong way for number two.
Manchester City have now been awarded five penalties this season.
Not that the German's lacked possession they just rarely troubled the host's rearguard. They looked most dangerous from a series of corners they earned and almost scored as City allowed an unmarked Lars Stindl to fire in a shot which Claudio Bravo got down well to save.
Previous to that City skipper Pablo Zabaleta had overhit a back pass which eluded Bravo but fortunately for the Argentinean only went for a corner.
Borussia only won four away games in the league last season but came out at the beginning of the second half looking to salvage at least a point but it was City who came closest early on when both Aguero and Sterling had chances.
The home side looked totally in control and should have made it three when Sterling was sent clear but the keeper deflected his shot wide and Gundogan was also denied by Sommer.
But City did make make the game safe, and the three points, with 13 minutes remaining as Agureo claimed his hat-trick, latching onto Sterling's through ball to round the keeper for his ninth goal in six games leaving boss Pep Guardiola with 7 consecutive wins at the start of his City career.
The home side's dominance was complete when substitute Kelechi Iheanacho made it four deep into stoppage time.
Man City: 4 (Aguero 8, 27 pen, 77, Iheanacho 90)
Borussia Monchengladbach: 0