Benarbia has failed to find his best form after starring in City's Division 1 promotion season last year but Keegan says Benarbia will only lose the captains armband if he asks to be relieved of it.
"We have talked about it but Ali was our heartbeat last year, he is our player-of-the-season and he is the most respected player at the club but he hasn't played well in the Premiership," Keegan told the club's official website.
"If Ali thinks it is too much then he has got to come to me. He is a very experienced player and certainly hasn't played well with the captaincy yet but I don't think you can blame him that for it."
"I just think that by his standards he has had an average start to the season. I think if everyone else was playing better then it would help Ali and everyone else."
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