After a number of errors this season, England goalkeeper Joe Hart was dropped in favour of Costel Pantilimon, and the Romanian did nothing to harm his cause on a quiet afternoon.
Pellegrini said: "My duty is to see, every week, which are the best players to play every game. We have a lot of games.
"This game, I thought Joe needed a rest. I think it will be useful for him.
"He has played every match for the last two and a half years here.
"We will work hard behind Joe so he can return to his normal performance level as soon as possible but (against Norwich) I thought the best goalkeeper was Pantilimon, nothing more."
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