Brazil's Olympic football coach, Andre Jardine, said on Thursday he wants to pick star forward Neymar for the Games in Tokyo later this year, but admitted it would be "difficult."
Neymar inspired Brazil to their first Olympic gold medal in football on home soil in 2016, ending a six-decade odyssey.
"Given we want to take the strongest possible squad, Neymar is our main player," Jardine said in an interview published on the Globo Esporte website.
Any potential participation for Neymar would need his French club Paris Saint Germain's agreement since they are under no obligation to release players for competitions not organized by football's main governing bodies, such as FIFA.
The chances of Neymar, 29, taking part are slim as he is due to play in the Copa America in Argentina and Colombia from June 13 to July 11.
The Olympic football tournament begins just 10 days later and is due to finish on August 8, two days after the start of the French Ligue 1 season.
Brazil have been drawn in Group D alongside Germany -- whom they beat in the 2016 final -- as well as Ivory Coast and Saudi Arabia.
Each Olympic football team is allowed 18 players of which only three can be over 23 years of age.