Aguero missed Argentina's round of 16 clash with Switzerland at the FIFA World Cup due to a thigh injury, with the striker having been hampered by the fitness issue throughout the tournament.
There had been speculation Aguero would leave Brazil due to the severity of the injury, but a day after watching his team emerge with a 1-0 extra-time victory over the Swiss in Sao Paulo, the 26-year-old was back on the training pitch.
Aguero completed sprints on his own and then took part in a practice match between the Argentina players that did not face Switzerland and a junior side that have travelled with Alejandro Sabella's men to help out in training.
The Argentina Football Association (AFA) confirmed on their website that their chief medico Dr Daniel Martinez expects Aguero to rejoin the main squad's training soon.
Meanwhile, Argentina cancelled their press conference on Wednesday to mourn the death of Argentine journalist Maria Soledad Fernandez, who died in a car crash when travelling to the team's base in Belo Horizonte from Sao Paulo.
Fernandez was the daughter of well-known Argentine journalist Miguel 'Titi' Fernandez.
Argentina held a minute's silence at training and AFA general secretary Juan Carlos Crespi explained that Sabella and his players were not comfortable completing the press conference.
"The players are extremely saddened by this death because they also feel affected as they are also children and they also have children themselves," Crespi told reporters.
"She was much loved."
Argentina striker Ezequiel Lavezzi expressed his condolences to the Fernandez family on Twitter.
"Immense grief over the death of the daughter of Titi Fernandez, a giant hug to him and all his family," Lavezzi tweeted.
