Manuel Pellegrini believes David Silva and Micah Richards will not be fit in time for the first Manchester derby of the season on Sunday.
Midfielder Silva has returned to training after a thigh strain, while defender Richards is also back on the training ground following a hamstring problem.
But Vincent Kompany is expected to start after coming through the Champions League win over Viktoria Plzen with no reaction to his groin injury.
"David Silva and Micah Richards are both back in training but Sunday is likely to come too soon for either to be involved in the squad," said City boss Pellegrini, who insists he is well aware of the importance of claiming local bragging rights.
"I don't need to be here to know just how important this game is to everyone," he added.
"I'm well aware. Football in England is different, I hope everyone enjoys it. It's a six-point game, these are two of the teams that will challenge.
"It's important not to be under too much pressure. David Moyes will be feeling some pressure after taking over from Sir Alex Ferguson, but some pressure is good.
"Yes, I know he had a good record with Everton against City. But with Villarreal I have a good record against him."
City have an identical record to United after taking seven points from their opening four games, the only surprise being a 3-2 defeat by newly-promoted Cardiff.
Pellegrini added: "We have had a good start, but not as good as we want. We must improve every game, it's difficult to change our style and the way we play, but winning makes you improve and we need to improve many things."