The incident took place during the half-time in Krasnodar, Russia on 14 November, according to the BBC. The former Atletico Madrid star scored his national side's second goal as Argentina went 2-0 up before the break.
Aguero's goal was the 36th goal for the La Albiceleste. With that goal, he surpassed Hernan Crespo and moved to the third spot in Argentina's all-time leading goalscorers' tally.
After the striker collapsed, he was rushed to the hospital and was released later.
The 29-year-old was taken to the hospital to undergo further tests, the Argentina federation confirmed via Twitter.
"Aguero suffered a collapse and was therefore taken to carry out routine studies merely as a precaution," a tweet read.
Goal.com report claims that Aguero lost consciousness in the middle of the match. However, the striker's club have denied those claims and confirmed Pep Guardiola's key player has been allowed to return to Manchester after suffering a "dizzy spell."
A statement on City's official website read, "Sergio Aguero has been cleared by doctors to return to Manchester as planned after suffering a dizzy spell during Argentina's 4-2 defeat by Nigeria in Krasnodar today."
"Sergio never lost consciousness, and was taken to hospital for precautionary medical checks. He will be assessed by the club's medical team ahead of this weekend's Premier League trip to Leicester City."
The clash at the Stadion FK in Krasnodar saw Nigeria come from behind to score three goals in the second half to clinch a victory over Argentina. Arsenal's Alex Iwobi was the star man for the African nation as he found the net twice as the Super Eagles managed a comeback.