They already knew they would be champions before the match kicked-off because in the earlier game at the Estadio La Portada in La Serena Argentina had lost 4-0 to hosts Chile.

Argentina had been the only side who could mathematically have prevented them from winning a seventh title and their third in a row.

The Brazilians maintained their unbeaten record in the tournament in Chile with another convincing performance at the Estadio La Portada in La Serena before a crowd of 12,000.

Mônica gave Brazil the lead in the 29th minute with her third goal of the championships.

Formiga doubled the lead at the end of the first-half before Mônica hit her second goal of the match in the 71st minute.

"We came here to do a great competition, not just win," said Brazil's top player Marta. 

Argentina need a six-goal swing in their favour if they were to pip Brazil to the title but that was out of the question following a disastrous first-half during which Camila Sáez and Maryorie Hernández scored in the eighth and 24th minutes before an own goal from an own-goal from Agustina Barroso left them 3-0 down.

Francisca Lara added a fourth at the end of the second-half to ensure Chile finished second and earn the second automatic qualification spot for next year's FIFA World Cup in France.

Brazil qualify for both the World Cup and 2020 Olympic Games in Tokyo but Argentina must now go into a playoff with a side from the Confederation of North, Central American and Caribbean Association Football region for a place at France 2019.