The Premier League champions expect to be without the striker until mid-September at the earliest after he fell awkwardly in their opening league game against Southampton last month. But Argentina coach Alejandro Sabella included Aguero in his squad for the World Cup qualifiers against Paraguay and Peru on Friday and Tuesday.
City boss Roberto Mancini labelled Sabella's decision to include Aguero "ridiculous", however the 24-year-old told reporters on his arrival: "I'm here until the Peru game. The knee still hurts at the moment and it bothers me, but maybe in two or three days the landscape will change. Now I'm going to see the doctors of the Argentinian Football Association."
Mancini accepted Argentina had a right under international rules to summon Aguero - and carry out their own medical assessment if necessary - but claimed it was a ludicrous situation.
Speaking on August 24, soon after the squad was announced, the Italian said: "It is impossible because Sergio needs a minimum of two weeks without training. After two weeks he can start again.
"If in one week if he could be ready to play it is different, but I think he needs another two weeks.
"He can go and fly back quickly. These are the rules and we need to respect them - they are ridiculous rules."
Aguero was happy to have been called up by Sabella despite the injury.
"It's always nice to be here with the guys," the former Atletico Madrid man added. "We knew from the Under-20s that this was a good group, and we must continue in this way."