The Premier League champions had been hoping to begin their European campaign with three points, but the North-West outfit were below par as they succumbed to a 2-1 setback on Wednesday night.
Fernandinho has acknowledged that there was tension between the squad and stand-in manager Mikel Arteta - due to Pep Guardiola's touchline ban - after the game, but feels that can be a positive for the team going forward.
The Brazil international is quoted by The Sun as saying: "There were strong words. Not just [Arteta] but from the players as well, but that is the best way to build a very good team. Of course, we are a good team but to compete in Europe you have to have something extra.
"I think it is a good point because we discussed it at half-time and before the game as well."
City's next fixture in the Champions League sees the club travel to Germany to face Hoffenheim at the start of October.