The Argentine was seething when he was left out of the starting line-up at Bournemouth before the international break.
He has endured a difficult relationship with Guardiola since the Spaniard took over as boss last summer.
It has led to speculation that Ageuro could try to leave the Etihad if he believes he is being messed about.
To make matters worse Guardiola was desperate to sign Arsenal’s Alexis Sanchez before the transfer window closed.
It raised further questions about Aguero’s long-term future at the club and it is not certain he will be recalled for today’s crunch showdown with title rivals Liverpool.
Aguero is regarded as an icon by the fans, but the City boss insists he cannot expect to be in the team all the time and has to accept his rotation policy.
Guardiola said: “I know it’s something special when a player who was never rotated, who’s always played, with the previous managers - it doesn’t matter what happens, he’s always in the line-up.
“I said many times, he’s going to play a lot of games and sometimes he’s not going to play. In my case he’s going to play like last season - a lot, a lot of games.
“I think he played, when fit, maybe 90 per cent of the games, especially in the important games, he was always there.
“So maybe one day we decide we’ll only play with one striker, sometimes with Gabriel (Jesus), sometimes with two, sometimes we’ll play with neither.
“Maybe Sergio and Gabriel won’t play and we’ll play a false nine. We will see. It depends on my ‘silly’ decisions.”
Manchester City boss Guardiola, who will be without Vincent Kompany (calf), has also told Raheem Sterling to show more mental toughness.
Sterling was hauled off at half-time during England’s woeful showing in Malta last weekend and Guardiola insists the winger needs to take the rough with the smooth.
He added: “The players have to learn about that. They have to learn that not everyone is going to play, that there are times when they are substituted.
“Maybe one or two players in the world can play 90 minutes every single week because they are so special and can win games.
“The other ones have to accept this and think about what they can do better next time for Gareth Southgate.
“The players have to go to the earth, on the grass and be humbled. Accept the manager’s decision and have respect for their team-mates.
“Why didn’t the guy play? Because he (manager) picked another one. What they have to do is try to think about what they can do to play more often.“It will happen here in the rest of the season for all the players - especially in my team.”
