Aguero lasted 24 minutes of Thursday’s game before he pulled up sharply, holding his left hamstring, while chasing a long ball.
Argentina coach Gerardo Martino said on City’s website that Aguero had arrived on international duty carrying a knock.
Martino says ”during the week we took good care of him. He was moving around the pitch well, but unfortunately he felt some discomfort and we are going to lose him.”
Martino says it is a different injury to the one Aguero was carrying with his club.
Aguero scored five goals in 20 minutes in his last game for City – a 6-1 win over Newcastle that returned his team to the top of the Premier League.