David Silva will be out for three weeks with a knee ligament injury in what is a sizeable blow to Manchester City ahead of Sunday's 168th derby and Wednesday evening's crucial Champions League match with CSKA Moscow.
Manuel Pellegrini is hopeful Yaya Touré, who has a groin issue, will be available for Manchester United's visit to the Etihad Stadium.
Pellegrini's team are suffering a loss of form, failing to win their last three games, losing the last two. The manager started both Silva and Touré in Wednesday's 2-0 Capital One Cup defeat to Newcastle United, when each suffered their respective problems.
Pellegrini said: “David has a problem in his ligament. Maybe he will be out around three weeks so he will not be available for the derby.
“Yaya has a small problem, we will see him tomorrow but I think he will not have any problems.”
The Chilean has previously described Silva as the team’s most vital player but he tried to downplay his absence. “He is a very important player but I think we have a squad and we have to replace him with another player,” he said, before discussing Touré’s indifferent form.
“I think we are a team and in that team we need top players in their performance always.”
Pellegrini admitted on Wednesday the side had a crisis of confidence.
“I just was talking about the normal performance of our team. We need to play faster than we are doing but in both games against West Ham (also lost) and Newcastle the best player of the other team was the goalkeeper.”
Can his team respond against United? “I think they know perfectly what we are doing and I am sure we will return to our normal performance.”
Pellegrini consistently talks of how his side will always play attacking football. Again, he signalled a refusal to change despite the results. “If I go one year ago, around the end of October, we have the same questions, when we won away just one game, I answer the same way,” he said.
Of the derby Pellegrini said: “It is a very important game but every game has just three points so it is very important for us to add just three points. Being a derby is more important for the fans. I expect that we are going to have a tough game against a very good team with very good players.”
Is the meeting with United the biggest match of the season? "It is difficult to talk about that. I think every derby is different from another one. Both teams are maybe not in their best moments of the season but always a derby is special," said the manager. "All the games are biggest games, especially when you have to win three points. Especially against Liverpool or Chelsea I always say they are games of six points."
