Bernardo Silva pulled a goal back midway though the second half after Leroy Sane's introduction breathed fresh life into City but Pep Guardiola's men went down to their fourth consecutive Champions League defeat - making them the first English side to endure such a run.
"If Pep had been on the touchline I couldn't tell you whether we would have won 5-0 or lost 3-0".
Whether Guardiola's absence from the dugout was behind City's ragged first-half display is hard to ascertain, but the team produced their worst performance for months while he was not standing in his technical area. In the second half we dominated and played in the opponents half and created many chances. We believe we can do better and tomorrow everything starts.
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City defender John Stones admitted the players were frustrated by their performance but insists they can still finish top of the group despite sitting below Lyon and Hoffenheim and Shakhtar Donetsk who drew in Ukraine earlier.
"We saw two very different halves".
But I think it is a very open Champions League - like it was last season but it will be again.
"I wouldn't like to use that as an excuse because we had that type of crowd in the Champions League before and we were able to win. Hopefully we can improve on the last two seasons because we came short". "The only reality is that we lost the game".
City were dominating possession ten minutes into the second stanza but they were yet to make unsafe attacks. It's the first match and it's vital for the group stage but he had a reaction to something that happened in a big game, they made a decision, we respect that and this is the situation.