Neymar left the field with a swollen ankle that needed treatment as Brazil beat Serbia 2-0 to begin their 2022 World Cup campaign on Thursday.
Brazil's team doctor confirmed that Neymar had sprained his ankle and that they need 24 to 48 hours to assess the extent of the damage.
Manager Tite said, “You can be sure: Neymar will play in the World Cup. You can be absolutely sure of this, Neymar will play in the World Cup!”
An injury scare for Neymar is nightmarish in what could well be his final World Cup tournament, medical staff treated an ankle which he appeared to roll under a challenge earlier on in the game.
His 2014 World Cup in his home country was ruined by a back fracture and Brazil also underwhelmed in 2018.
But with the Selecao coming into this tournament as one of the favourites, many tipped Neymar to finally steal the show on the world stage with his mesmeric talent.
Brazil are next in action on Monday when they play Switzerland in Group G, although it remains to be seen whether or not the 30-year-old Paris Saint-Germain forward will have recovered in time.