Doubts have persisted over the first appearance of Brazilian star Neymar at the FIFA World Cup, currently being held in the United States, Mexico and Canada.
Neymar underwent new medical examinations on his injured right leg on Monday evening local time.
There had been hope that Neymar would return to training on Monday evening, but the Santos player did not join his teammates and instead went to have his right calf examined. The Brazilian Football Confederation did not immediately disclose the results of the tests.
Neymar, 34, who is taking part in the World Cup for the fourth time, has been sidelined since sustaining an injury with Santos in the Brazilian league on 17 May.
Brazil play Haiti on Friday evening local time in Philadelphia in the second round of Group C at the tournament, which also includes Morocco and Scotland.
Neymar has not taken part in any full training session with Brazil so far since the five-time world champions began their World Cup preparations in Morristown, New Jersey.
Brazilian media reported that the national team's medical staff are hopeful that Neymar will be fully fit to participate in the knockout rounds of the tournament.
The prospect of Neymar's return took on greater significance following Brazil's disappointing 1-1 draw with Morocco in their World Cup opener on Saturday evening.
Nevertheless, Neymar added a special glitter to the match held at MetLife Stadium in East Rutherford, New Jersey, as he was spotted on the touchline before kick-off greeting celebrities such as rapper Travis Scott and seven-time Super Bowl champion Tom Brady.