Aguero believes Tevez could be a key player for City in the Premier League title race.
Tevez has returned to City after having spent more than three months in Argentina without the Premier League side’s permission.
“Tevez is a big footballer and nobody doubts it. The day he returns [to the team] will be a big day for us,” Aguero said in The Sun.
“I prefer things with him in the squad because he is a very important player for us. I spoke a few times with him while he was absent. He is a super professional and it was up to him to decide about his future.
“I am happy he is back. I think his return could be important for us in the decisive period of this season.
“He has been one of the best forwards in world football over the last few years. City need all the players we have to try and win titles.”