Since Santiago Solari took over at Los Blancos, Vinicius has risen to prominence with some impressive displays for the first team.
There were also call-ups for Lucas Paqueta, who has impressed at AC Milan while West Ham United star Felipe Anderson has earned a re-call.
Selecao will take on Panama on 23 March, before they lock horns with Czech Republic three days as they continue preparation for the Copa America.
Goalkeepers: Alisson (Liverpool), Ederson (Manchester City), Weverton (Palmeiras)
Defenders: Alex Sandro (Juventus), Danilo (Manchester City), Filipe Luis (Atletico Madrid), Eder Militao (Porto), Dani Alves (Paris Saint-Germain), Marquinhos (Paris Saint-Germain), Thiago Silva (Paris Saint-Germain), Miranda (Inter Milan)
Midfielders: Allan (Napoli), Arthur (Barcelona), Philippe Coutinho (Barcelona), Casemiro (Real Madrid), Fabinho (Liverpool), Felipe Anderson (West Ham), Lucas Paqueta (AC Milan)
Forwards: Everton (Gremio), Roberto Firmino (Liverpool), Gabriel Jesus (Manchester City), Richarlison (Everton), Vinicius Junior (Real Madrid)