Milan striker Ricardo Oliveira has been recalled to Brazil's squad after an impressive campaign in Serie A.
The former Real Betis and Valencia front man replaces Rafael Sorbis, who has pulled out of Dunga's squad for forthcoming friendly internationals against Chile and Ghana due to injury.
Oliveira's recall is likely to give the rapid forward a tonic for the rest of the campaign, particularly when coupled with the fact he missed the World Cup last year through injury.
Another new face to Dunga's ranks is the previously uncapped goalkeeper Cassio, who impressed greatly in helping Brazil win the South American Under 20 Championship in January.
Despite having not yet broken into Gremio's first team, Cassio is rated as a key player for the future, with his fast-track to the international ranks catching the 19-year-old by surprise.
"To be honest, I can't believe it," said Cassio. "I think it will only become reality when I meet the players and the coaching staff."