Neymar is responding “very well” after undergoing knee surgery but doctors do not know when the Al-Hilal forward will return to playing.
Recovery from an ACL rupture or tear can be eight to 10 months.
Rodrigo Lasmar, Brazil’s team doctor, said Neymar is fully committed to regaining full fitness.
“He has demonstrated, from the first moment, that he is following what we are proposing,” Lasmar told a news conference in Sao Paulo on Monday.
Neymar was taken off on a stretcher in tears during Brazil’s 2-0 defeat by Uruguay after landing awkwardly following a challenge in the first half.
He moved to Saudi Pro League side Al-Hilal in the summer from Paris St-Germain for 90m euros (£77.6m) plus add-ons but has only played five games because of muscle injuries.
