Wilfried Bony has hit out at Pellegrini for dropping him in the 2-1 loss to Arsenal.
Bony, has scored three times in four games, with Aguero out injured.
And Aguero was picked ahead of Bony in the match against Arsenal.
“I’m disappointed that I didn’t start,” Bony said. “I’m not the coach. The coach does what he thinks is best for the team.
“He just has to choose 11 players. So when I come on I just try to do my best to try to score or to give an assist to the other players to score to help the team to win.”
When asked whether he thought he had done enough for another start, Bony replied: “I think so. He [Agüero] is coming back from injury. He hasn’t played for a couple of weeks.”
Monday night’s loss leaves Manchester City six points behind league leaders Leicester ahead of Saturday’s meeting with Sunderland at the Etihad Stadium.