Match ends, Argentina 2, Nigeria 4.
Sergio Aguero was taken to hospital after fainting in the dressing room at half-time in Argentina's 4-2 defeat by Nigeria in Krasnodar, Russia.
The Manchester City striker had scored to put his side 2-0 up in the first half, but Arsenal's Alex Iwobi found the net twice as Nigeria came back.
The Argentina FA said the 29-year-old had been taken to hospital to "carry out routine studies as a precaution".
They later confirmed that Aguero had been discharged from hospital.
"He is already in the hotel along with the rest of the team," they tweeted.
After the match Argentina manager Jorge Sampaoli said Aguero had "got dizzy and had to leave".
In a statement City said he had been cleared by doctors to return to Manchester as planned "after suffering a dizzy spell" during the match.
"Sergio never lost consciousness, and was taken to hospital for precautionary medical checks," the club said. "He will be assessed by the club's medical team ahead of this weekend's Premier League trip to Leicester City."
Aguero, who became City's all-time leading goalscorer earlier this month, had recently returned to action after he suffered a rib injury in a car crash in Amsterdam in September. He was injured when a taxi he was travelling in after attending a concert crashed into a lamp post.
In Wednesday's international friendly, Leicester's Kelechi Iheanacho netted with a free-kick and Brian Idowu was also on the scoresheet for the Super Eagles, who had fallen behind to strikes from Aguero and Ever Banega.
Analysis - just a little scare
Tim Vickery, South American football expert
Aguero was already feeling unwell during the first half against Nigeria and at half-time in the dressing room he had a blackout.
Perhaps it was a premonition of how badly they would play in the second half. It seems it was just a little scare.
- 4PezzellaSubstituted forInsúaat 80'minutes
- 21DybalaSubstituted forBelluschiat 63'minutes
- 20Lo CelsoSubstituted forGomezat 58'minutes
- 26PavónSubstituted forPerottiat 77'minutes
- 11Di MaríaSubstituted forRigoniat 76'minutes
- 9AgüeroSubstituted forBenedettoat 45'minutes
- 1AkpeyiSubstituted forUzohoat 45'minutes
- 12ShehuSubstituted forEbuehiat 45'minutes
- 6BalogunSubstituted forOmeruoat 61'minutes
- 2AinaSubstituted forIdowuat 45'minutes
- 14IheanachoBooked at 17minsSubstituted forMusaat 70'minutes
- 18IwobiSubstituted forKayodeat 87'minutes
- 3Henry Agbo
- Vladislav Bezborodov
- Shots on Target
Second Half ends, Argentina 2, Nigeria 4.
Attempt blocked. Fernando Belluschi (Argentina) right footed shot from the left side of the box is blocked.
Éver Banega (Argentina) wins a free kick on the right wing.
Foul by Johan Ogu (Nigeria).
Attempt missed. Nicolás Otamendi (Argentina) header from the centre of the box misses to the left. Assisted by Emiliano Rigoni with a cross following a corner.
Corner, Argentina. Conceded by William Troost-Ekong.
Corner, Argentina. Conceded by Johan Ogu.
Enzo Pérez (Argentina) wins a free kick on the left wing.
Foul by Wilfred Ndidi (Nigeria).
Attempt missed. Éver Banega (Argentina) right footed shot from outside the box is high and wide to the left from a direct free kick.
Enzo Pérez (Argentina) wins a free kick in the attacking half.
Foul by Ahmed Musa (Nigeria).
Attempt blocked. Fernando Belluschi (Argentina) right footed shot from outside the box is blocked. Assisted by Nicolás Otamendi.
Attempt missed. Alejandro Gomez (Argentina) right footed shot from outside the box misses to the left. Assisted by Emiliano Rigoni with a cross.
Substitution, Nigeria. Olarenwaju Kayode replaces Alex Iwobi.
Offside, Nigeria. Ahmed Musa tries a through ball, but John Obi Mikel is caught offside.
Corner, Nigeria. Conceded by Emiliano Rigoni.
Foul by Diego Perotti (Argentina).
John Obi Mikel (Nigeria) wins a free kick on the right wing.