"Only music and football can attract 80,000 people to a stadium, but a concert has just one artist, while football has 22," said FIFA Secretary General Jerome Valcke at Brazil's Maracana Stadium.
"We are here to break down barriers and show that through sports and music we are one," said Pitbull, a Cuban-American rapper whose real name is Armando Christian Perez, at the event held here five months before kickoff.
Leitte said the song would show off her country's love affair with musical and sporting rhythm.
"Music is my passion and football is the passion of the Brazilian people," the singer said.
"We want to show the passion and the culture -- that's what we have in this record. We are in the finishing phases.
"This music will be a golazo!" she added, using a term which means "great goal" in Spanish and Portuguese.
Lopez was not in Rio for Thursday event.
Former Brazilian skipper and World Cup winner Cafu said the song "incorporates the rhythms of Brazil and of the Brazilian people -- people will dance to the World Cup beat."
Alexandre Schiavo, president of FIFA commercial partner Sony Music Brazil, also praised the happy marriage between football-loving Brazil and its infectious music.
"Brazilian music is very rich and music and football is a passionate combination," Schiavo said.
Organizers hope the recording enjoys similar success to Colombian star Shakira's "Waka Waka" signature tune from the last World Cup, held in South Africa in 2010.
That track was a huge success, notching up more than half a billion Youtube views.