Aguero, 33, opened the scoring against EU Cornella at Barca’s training ground as The league side were held to a 2-2 draw by the third tier opposition.
Aguero joined Barca in June after his City contract expired after a decade at the Etihad. However, a calf injury in August means he has yet to make his official debut for his new club.
He finally returned to full training earlier this week after a two-month absence and began the draw with Cornella, playing for half an hour, as recommended by the club’s medical staff.
Ronald Koeman must now assess whether Aguero is ready to be included in the squad for Sunday’s LaLiga game against Valencia.
Ansu fati, who returned to competition before the international break, was also given a few well-deserved minutes, although the match was judged too early for Ousmane Dembele, who resumes a light training after three months of absence.
After Valencia, Barca will host Kiev on Wednesday in the Champions League, where they have lost their two games so far and then face Madrid in the first Classic of the season on October 24.
It is shaping up to be a key week for Coach Koeman, who was gave more time to turn the tide on his side by President Joan Laporta earlier this month despite a one-win streak in six games.