Late goals from Philippe Coutinho and Neymar eased the tension of a hard-fought Group E clash in St Petersburg, with Tite's side bouncing back from their disappointing opening draw against Switzerland.
But he also underlined the struggle he had faced to reach the tournament after suffering a metatarsal injury, a hardship with which Corinthians defender Fagner can identify.
"Neymar has gone through a lot," said the diminutive full-back, who was filmed celebrating wildly when his call-up was confirmed.
"Two weeks before I was camped for the World Cup, I had an injury. So after that I wasn't sure if I would be here for Russia.
"Different people react differently. Perhaps that was his outburst.
"We know what we've gone through to get there. It's difficult to judge. He was playing back a movie in his mind. He scored a goal and was in a World Cup again.
"That's the dream for a Brazil player. Being able to wear Brazil jersey will make us stronger and stronger."
Next up for Brazil is Wednesday's clash with Serbia and Coutinho is set to play another key role.
While Neymar has dominated headlines, Coutinho has earned two man-of-the-match performances with two goals.
"He is just great. Coutinho is a phenomenal player," Fagner said. "We know that he can create wonderful situations. We're very happy that he is going through a very good moment."
England stormed into the knockout round of the showpiece tournament as a result of their Group G demolition in Nizhny Novgorod.
"England are a great team. We know how strong they are and their football is," Fagner added. They have great players.