Once the tear gas had settled and the red-clad protesters had fled, the Sao Paulo man stuck his head out the window and shouted a message encapsulating the divide troubling Brazil on kick-off day: "Today there will be a Cup!"
The protesters' slogan that "There won't be a Cup" has dogged Brazil for the past year, marring preparations for the opening match in Sao Paulo's shiny new -- if chronically delayed and over-budget -- Corinthians Arena at 5:00 pm (2000 GMT) Thursday.
Brazil's ambivalence toward the World Cup was on full display as the country geared up for the game, the sea of green and yellow in some areas contrasting with the clashes between police and protesters in Sao Paulo and fears of more nationwide.
In cities across the country, many morning commuters proudly wore the number 10 jersey of star striker Neymar or decked themselves out in the colors of the flag, whether with green-and-yellow shirts, dresses, skirts or flowers in their hair.
In Rio de Janeiro, there was a festive atmosphere as tourists took in the breathtaking views from Mount Corcovado, where an enormous Brazilian flag adorned the base of the iconic Christ the Redeemer statue.
Football fans from around the world sporting the colors of their teams gathered around the monument, one Argentine proudly flying a flag proclaiming "Yes We Can."
In Sao Paulo, where authorities have declared a holiday, fans began congregating early in the morning outside the hotel where the Brazilian team were staying.
Monica Seixas had gone there to take a picture with her dog, both decked out in green and yellow.
"I love the World Cup. I always follow it and now I'm super excited that it's happening in Brazil," said the 57-year-old engineer outside the Hotel Pullman Ibirapuera in the south of the city, which had a heavy police presence around it.
"We've been here since 8:00 am. My son wouldn't let me sleep. He wanted to come see the 'selecao,' and we're not leaving until we see them," said IT specialist Paulo Loria, 49.
Riot police determined
That festive move seemed a world away from the clashes outside the Carrao subway station on Sao Paulo's east side, but in fact the two places are just a few kilometers apart.
Gregory Leao, a 27-year-old law student at the protest, said the demonstrators wanted to invade Corinthians Arena.
"The objective is to put an end to the World Cup. We realize we're not going to achieve it, but we believe Brazilians should rise up," he said.
Brandishing a red banner with the slogan "Without rights there will be no Cup," the protesters numbered only a few dozen and didn't look capable of invading much of anything.
But riot police showed their determination not to let them mar the nation's big day, firing tear gas, stun grenades and rubber bullets to break them up and detaining one shirtless man who refused to flee.
In Rio, striking airport ground staff -- the latest to join the wave of strikes ahead of the tournament -- invaded the road to the international airport and briefly blocked it off.
Their protest created a long traffic jam, causing some worried travelers to exit their vehicles and run toward the airport to catch their flights.
Around 500 protesters in downtown Rio also sought to revive the momentum of the million-strong protests that shook Brazil last year during the Confederations Cup -- a World Cup dress rehearsal -- shouting "FIFA go home!"
In some of the 12 host cities, the World Cup atmosphere was visibly tense.
In Belo Horizonte, many banks and businesses around the central square were closed ahead of a protest planned for midday.
Host city Curitiba also had little World Cup spirit on display.
There was little green and yellow on the streets, and some vendors were selling T-shirts with the slogan "F*** World Cup 2014 in Brazil."