The 26-year-old also came in for criticism last season although he did end the campaign as part of the tightest defence in the Premier League.
"The past is past," Pellegrini said. "Of course there is last season but we have a new season now.
"I hope Joe will have the performance we all know he has had in his whole career. We will see every match what will happen with him but I have a lot of trust in him. I don't worry about him.
"For me always we play the players who are giving the best performance and in the best moment.
"My teams do not play by name, they play by performance. For the whole team, the 22 players are exactly the same. I am not talking about anyone special."
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