The Argentina striker has not featured for the Citizens since suffering a hamstring injury during the 2-1 defeat at Barcelona earlier this month and will miss the game along with defender Matija Nastasic, who has a knee problem.
“We will see next week how Aguero improves,” said Pellegrini.
Arsenal have very good players and we will need to play a very good game if we are to win
“The squad [to face Arsenal] is the same as last week. Matija Nastasic and Aguero will miss out. Micah Richards and Dedryck Boyata will work here.”
Pellegrini’s title-chasing City side head into Saturday’s clash at Emirates Stadium on the back of a comprehensive 3-0 win over derby rivals Manchester United on Tuesday night.
But the Chilean has warned his players that they will face a tough test against Arsene Wenger’s men.
“It was very important for the fans, club and players to win the derby,” he continued.
“Now we must continue and look to win the next match. Arsenal have very good players and we will need to play a very good game if we are to win.”
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