Barca had to wait until the 68th minute to break down their city rivals when Alexis Sanchez was left with a simple tap-in after clever work from Neymar.
"There are matches with good phases and bad phases," said Iniesta.
"We're counting nearly all of our games as victories and that should give us confidence to improve and keep on winning games.
"I don't have the impression that we're playing poorly."
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