The Haugesund defender got to Manaus on Tuesday afternoon and has lodged himself at the team’s hotel.
Troost-Ekong, a 22-year-old central defender with the Super Eagles, has been brought in as cover for the team after their poor outing at the Suwon Invitational Tournament in June.
He was allowed to return to Norway from Atlanta by coach Samson Siasia for a domestic game at the weekend before flying via Amsterdam to Sao Paulo and on to Manaus.
The player told Goal that it was a tiring trip but he was in a good mood ahead of the tournament.
Another player that would fly in separate from the squad is Umar Aminu who also was given special permission by the coach to leave camp early.
The remaining members of the squad will depart Atlanta on Tuesday via a chartered flight en route for Manaus.
Nigeria will play their first game against Japan in the wee hours of August 5 (2am) as they attempt to win Olympic gold 20 years after their illustrious seniors won the title in Atlanta.