The Liverpool pair were named in Tite’s squad for the tournament on home soil while Fabinho was left out, with the midfielder instead training at Melwood over the weekend.
The No. 9 was also an ever-present, scoring two and assisting three as Brazil set up a clash with Peru in Rio de Janeiro.
Brazil began strongly, and it was Firmino’s industry which helped set up their second goal, winning the ball back with a fine sliding tackle before feeding it to Arthur, who laid on Gabriel Jesus for the finish.
? This tackle from Firmino to begin Brazil's attack for their 2nd goal is incredible
— Premier Sports ? (@PremierSportsTV) 7 July 2019
Jesus had already set up Cebolinha’s opener with brilliant footwork on the right, but then with the scores at 2-1 after the break, his night ended early.
The City striker was sent off in controversial fashion, after picking up two yellow cards, and he vented his frustration by knocking over the VAR monitor on his way to the tunnel.
Firmino was brought off minutes later with Richarlison taking his place, and his replacement was on hand to secure victory in the closing stages with a penalty after Cebolinha was brought down.
There were wild scenes at full-time as Brazil clinched their first trophy in 12 years, with both Alisson and Firmino key to doing so.
Remarkably, Paolo Guerrero’s first-half penalty for Peru was the only goal Alisson conceded across the whole tournament, but while his perfect run ended he still finished Copa America with the Golden Glove.
For Firmino, the distinction comes as being the player who directly contributed the most goals (five), edging out Jesus (four) and top scorer Cebolinha (four).
This victory saw the pair lift their second trophy of a remarkable season, and they can now head on a well-earned break before rejoining the Liverpool squad for pre-season.
They are expected back in time for the Community Shield clash with City on August 4.