Aguero will miss Premier League fixtures against Leicester City, Watford, Arsenal and Hull City. The Argentine will not be available for selection until the game at Liverpool on December 31.
Iheanacho, who scored in City’s 1-1 draw with Celtic in the Champions League on Tuesday, says he has received words of encouragement from Aguero.
“Before we played Celtic he said that it’s up to me now to fill that gap, to carry the team along,” the Super Eagles forward told reporters.
“He’s telling me I should do very well and they are words of encouragement from him. So I’m going to do it.
“It’s a big opportunity for me now. Sergio’s not around so I have to take responsibility. I need to work really hard to prove myself to the team and help get these points we need.”
Manager Pep Guardiola has already said Iheanacho is not under pressure to replace Aguero.
