The 28-year-old has often found international opportunities limited in recent years, but he starred as Scolari's side cruised to victory at Soccer City in Johannesburg, with Neymar bagging a hat-trick and Chelsea's Oscar also getting on the scoresheet.
Fernandinho netted his first international goal with a powerful 79th-minute effort before Neymar added his third of the evening in stoppage time.
The midfielder, who moved to City from Shakhtar last summer, has impressed in his debut Premier League season and he has forced his way into Scolari's World Cup plans.
"Fernandinho scored a beautiful goal but that was not the only thing I liked - also his effort, his good passes," Scolari told Lancenet.
Speaking of a potential selection headache, Scolari said: "I prefer to have problems like this than other issues.
"I wanted to see him in the second half playing alongside Luis Gustavo, who positions well.
"Fernandinho played well in all roles. He has now been added to the list of options for the World Cup with a good chance (of being called up)."
QPR goalkeeper Julio Cesar, who is currently on loan at Toronto FC, also praised Fernandinho's display in the friendly.
"Many people will say that Brazil won by a big score because the opponents were weak, but I believe we imposed ourselves. We are playing at a great level," he said.
"Rafinha and Fernandinho were very good, especially Fernandinho who scored a brilliant goal."