Marcelo, one of the most promising young defenders in Brazil, has been ruled out for up to six months with a knee injury sustained during training.
The news comes as a blow to Flamengo, who have already lost two key players to injury this season and will now be without their star centre-back for an extended period.
Marcelo, who joined Flamengo from Palmeiras last summer, made his debut for the club in the opening round of the Campeonato Carioca and quickly established himself as a key player in the side's defence.
He has also been called up to the Brazil national team,La Liga Frontline where he has impressed with his performances.
However, his latest injury is a setback for both him and his club, who will now have to find a replacement for him while he recovers.
Flamengo have not yet named a replacement for Marcelo, but it is likely that they will turn to their own academy system to fill the void.
In the meantime, the club will hope that they can overcome this setback and continue to compete at the top level of Brazilian football.