Prior to the international break, the champions took on their city rivals in the Premier League and dominated the game from start to finish, culminating in a 2-0 victory for Pep Guardiola’s side.
An own goal from Eric Bailly and a Bernardo Silva effort did the magic for Manchester City, who became the first side to record eight victories at Old Trafford.
Guardiola was so impressed with his side’s dominance that he did not make a single substitution as the champions climbed to second positon on the table, three points behind leaders Chelsea.
De Bruyne says Guardiola was unsure how Man United were going to set up, which forced him to abandon training altogether.
"The day before a game we usually train tactically, based on how the opponent play," De Bruyne told the MidMid podcast.
"Before United, Pep said: 'We don't know how they are going to play. We shall see'. And we stopped training after 10 minutes or so.
"Often Pep knows how the opponent is going to play. This time he didn't know, so he didn't know what to do. We have done what we always do, but he didn't know beforehand if they would play with 5 at the back. With four. A diamond in the middle. With 3 upfront."
Man City will host Everton after the international break.
